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Man of the Hour

James B. Conant, Warrior Scientist



About The Book

“Gripping…an outstanding portrait” (The Wall Street Journal) of one of the most influential men of the greatest generation, James B. Conant—a savvy architect of the nuclear age and the Cold War—told by his granddaughter, New York Times bestselling author Jennet Conant.

James Bryant Conant was a towering figure. He was at the center of the mammoth threats and challenges of the twentieth century. As a young eminent chemist, he supervised the production of poison gas in World War I. As a controversial president of Harvard University, he was a champion of meritocracy and open admissions. As an advisor to FDR, he led the interventionist cause for US entrance in World War II. During that war, Conant oversaw the development of the atomic bomb and argued that it be used against the industrial city of Hiroshima in Japan. Later, he urged the Atomic Energy Commission to reject the hydrogen bomb and devoted the rest of his life to campaigning for international control of atomic weapons. As Eisenhower’s high commissioner to Germany, he helped to plan German recovery and was an architect of the United States’ Cold War policy.

Now New York Times bestselling author Jennet Conant recreates the cataclysmic events of the twentieth century as her grandfather James experienced them. She describes the guilt, fears, and sometimes regret of those who invented and deployed the bombs and the personal toll it took. “A masterly account…a perceptive portrayal of a major player in world events throughout the mid-twentieth century” (Publishers Weekly), Man of the Hour is based on hundreds of documents and diaries, interviews with Manhattan Projects scientists, Harvard colleagues, and Conant’s friends and family, including her father, James B. Conant’s son. This is “a most serious work, well written and evocative of an era when the American foreign establishment exuded gravitas…[a] new, relentless, and personally invested account” (The New York Times Book Review).


Man of the Hour CHAPTER 1 Atomic Pioneer
Here sits a man who perhaps is carrying a bit of the atomic bomb in his waist-coat pocket.

—Vyacheslav Molotov to JBC

Christmas Eve, 1945. Moscow was blanketed under a thick coat of snow. There were almost no cars about. His driver eased down ruined streets that made it look like a country still at war. The winter blizzards had begun before the rebuilding had gotten under way, and now it would have to wait for the thaw. Unfinished buildings stood frozen in time. Stores looked dark and uninviting, and appeared to offer little for sale. Even so, huge numbers of people gathered outside the shops and still more filled the crowded sidewalks, all carrying parcels. Most were poorly dressed, covered heads bent against the swirling white. Over twenty-seven million Soviet citizens died defeating the Nazis, nearly a third of the country’s former wealth was gone, but Russia was already on the rebound. There were children everywhere. Babies—so many babies—bundled up within an inch of their lives against the bitter cold. Despite its drab appearance, the capital was alive and teeming with humanity. James Conant was a Yankee from hardy New England stock, but he had to admit he was impressed with the Russians. They were a tough race, tested by war, insurrection, and an unforgiving climate. “There is no foolishness in this nation,” he wrote in his diary. “Nothing soft.”

As the embassy car approached the gates of the Kremlin, Conant peered up at the gloomy fortress-like complex on the Moskva River that was the seat of the Soviet government. Situated in the heart of old Moscow, bordered by Red Square to the east, and Alexander Garden to the west, it consisted of four palaces, four cathedrals, and some twenty towers enclosed within red turreted walls. The famous citadel had been the imperial residence of the czars for centuries, its opulent interior structures torn down and rebuilt on an ever-grander scale by a succession of monarchs until the Revolution of 1917. Even the Bolsheviks had been unable to resist the urge to glorify their rule. When Vladimir Lenin finally made it his headquarters, he stripped the golden eagles of the old regime from the towers and replaced them with the gleaming red stars of the new Communist order. Now the Russian dictator Joseph Stalin called the Kremlin home, and had chosen the savior’s birthday to hold a reception in honor of his victorious allies. Since the atheist Soviet state had banned Christmas as a bourgeois tradition, however, the timing was not nearly as ironic for their host as it was for his guests.

The dinner was held in a cavernous banquet hall. America’s secretary of state, James Francis Byrnes, and Great Britain’s foreign minister, Ernest Bevin, took their places on either side of Stalin, each flanked by a twelve-man delegation. The Soviet commissar of foreign affairs, Vyacheslav Molotov, was also in attendance, along with various members of the Politburo. The Russians aimed to impress: there were boats of caviar, smoked sturgeon, guinea hen, beef, and lamb and other delicacies, arrayed like a flotilla of silver down the long table, along with oceans of booze—champagne, wine, brandy, and, of course, vodka. As soon as the guests were seated, the toasts began. According to custom, each course was preceded by a toast and a tumbler of vodka, which courtesy required be responded to in kind, toast for toast, drink for drink. One after another, the official toasts were drunk—to their nations, peoples, armies, leaders, and innumerable government functionaries present that night. As each ponderous speech of welcome and good wishes had to be translated by an interpreter, even the short toasts seemed long. Conant, unused to so much alcohol, found it hard to relax. If one of the Russian officials were to drink to his health, he doubted his vodka-soaked brain would be able to formulate a suitable reply.

He was still not sure what he was doing there. Two weeks earlier, he had stopped by his Washington office for a few hours when he received a call that the secretary of state was “anxious to speak to him right away.” When he reported to Byrnes’s office, he was informed an emergency had arisen. The secretary was leaving for Moscow in two days’ time and wanted Conant to accompany him. The main purpose of the trip was to try to talk to the Russians about international control of the atomic bomb. Byrnes, a short, energetic man with sharp eyes, explained that he needed a bomb expert. Vannevar Bush, the director of the Office of Scientific Research and Development, had fallen ill. Conant, the science administrator who along with Bush had led the Manhattan Project, and had been chiefly responsible for overseeing the development of the revolutionary new weapon, was an obvious choice. His distinguished war service, together with his stature as president of Harvard University, meant he would be able to argue effectively with the Soviet experts. Would he go?

Conant was immediately intrigued by the prospect. He knew a great deal was at stake. Since the first bomb fell on Hiroshima in August of that year, America’s atomic monopoly had divided their countries and cast a pall over postwar peace negotiations. Conant believed the only way to ensure peace was for the United States and the Soviet Union, which until very recently had been allies, to work out their differences and come to some arrangement regarding atomic energy and weapons of mass destruction. Even though it meant that the United States would have to give up its sole possession of the atomic “secret,” the internationalization of nuclear weapons and their production was the only way he could see to prevent an arms race. Nuclear intimidation was not the way to achieve national security. Having had a hand in unleashing this tremendous destructive force, Conant felt a strong obligation to help see it contained. No one understood better than he the need to outlaw the bomb’s use in future conflicts, for that way led only to certain disaster and Armageddon.

At the same time, he had no official standing. He was a scientist, not a politician. He had only just returned to Harvard full-time after a four-year absence during the war, and knew accepting another high-profile government assignment would infuriate the university trustees. By then, he had also spent enough time in Washington to worry about what he might be getting himself into by signing up for Byrnes’s Moscow mission. There would be a price to pay, either way.

After some deliberation, he decided he had no choice but to accede to the secretary of state’s request. He rushed back to Boston and grabbed some winter clothes, and was back in Washington by Wednesday in time to leave with the American delegation from National Airport. They crossed the Atlantic in a special C-47 that was put at the secretary of state’s disposal, overnighted in Frankfurt, and the next morning took off for Moscow via Berlin despite a warning that a front was closing in. They flew straight into the snowstorm, veering off course and getting lost. For a hair-raising hour or more, they flew blind, searching for lights—any signs of human habitation—while their fuel was running low. The decision was made that if the pilots could not find the city in the next ten minutes, they would have to turn back. Seconds later, the plane banked sharply, and Conant assumed they were headed for Berlin. Just then, the clouds parted, and the sprawling outskirts of Moscow came into view. Everyone let out a sigh of relief when they landed, even though it was the wrong airport. The Russian officials who met them kept asking why they had attempted such a risky flight. No one had an adequate answer.

The hastily improvised Moscow Foreign Ministers Conference was Byrnes’s last-ditch effort at atomic diplomacy. For months, the Soviet leaders had done everything they could to frustrate his attempts to use America’s monopoly on the bomb as leverage in the peace talks. The failure of Byrnes’s gunslinger-style tactics at the Foreign Ministers Conference in London that fall had been an embarrassment. The negotiations had been fruitless. Rather than treat the bomb with the respect and fear Byrnes expected, the Russians had ridiculed the metaphorical bulge in his jacket in social gatherings while refusing to address it seriously in formal sessions. Stalin had feigned indifference, and issued a statement saying that it was only a weapon to frighten the weak-willed. Molotov, a master at subterfuge and delay, adopted the same line, and delighted in denigrating the bomb at every turn.

President Harry Truman was losing faith in Byrnes, who had been dubbed Roosevelt’s “assistant president” by the press, a title that did not sit well with his new boss. Even an old soldier like Henry Stimson, the outgoing secretary of war, warned that the bomb was a game changer, and it was a mistake to use it as a lever of pressure to extract internal political changes and the granting of individual liberties. Such changes took time, and the United States could not afford to delay reaching an agreement on the bomb. “If we fail to approach them now,” Stimson argued, “and merely continue to negotiate with them, having this weapon rather ostentatiously on our hip, their suspicions and their distrust of our purposes and motives will increase.” They could not afford to waste this chance at world peace.

Desperate to reach some sort of compromise, and in the process score a diplomatic triumph that would redeem his reputation, Byrnes decided to take a more conciliatory approach. He would journey to the Soviet capital and take his case directly to Stalin. With luck, the home turf advantage would make the Russians more amenable to the need for international action so that this unprecedented form of power did not become a postwar threat to the world.

In Moscow, however, things did not go much better. Molotov was as obstructionist as ever. He persisted in making flip remarks about America’s atomic ace in the hole, clearly aimed at letting Byrnes know the Soviet Union would not be cowed into making political concessions. As in the Potsdam and London conferences, no member of the Soviet delegation showed any interest in discussing the bomb, or the proposed resolution for the creation of a United Nations commission to control atomic energy. The Soviets never demanded the sharing of the atomic “secret,” or objected to the need for an inspection system—something that would not be popular in the United States, let alone in Russia—to police all military and industrial plants to prevent abuses and safeguard against any nation clandestinely stockpiling weapons.

Conant had felt it was imperative the Soviets should know about this radical new method of decisive warfare, and was surprised to find there were no technical questions, no arguments. Although his arrival in Moscow had been covered at length in the local press, not a single Soviet scientist had sought him out. Molotov, during the course of a dinner at which he was host, had suggested that perhaps the great American chemist, who was also president of a great American citadel of learning, should address the University of Moscow on the subject of atomic energy. The following day, however, Molotov withdrew the invitation, stating that he had no authority to make such an offer and was “only trying to be pleasant.” If Byrnes had been hoping the presence of the illustrious atomic pioneer at the negotiations would spark debate about the future of the bomb, his ploy fizzled. Conant felt like he might as well have stayed home for all the good he had done. He never suspected that the reason behind the Soviets’ apparent disregard was to prevent any chance of an inadvertent leak by Russian scientists that might alert the US delegation that they were feverishly at work on an atom bomb of their own.

Conant had lost count of how many times they had drained their glasses when Molotov, who was acting as master of ceremonies, rose slowly to his feet. Raising a freshly filled glass, a broad grin on his round, bespectacled accountant’s face, he proposed to the assembled party that they had all had enough to drink to allow them to “speak of secret matters.” Turning to Conant, he said mischievously, “Here sits a man who perhaps is carrying a bit of the atomic bomb in his waist-coat pocket, with which he could blow us all to tiny pieces—”

Before he could finish, Stalin jumped to his feet and broke in angrily, “Comrade Molotov, this is too serious a matter to joke about.” After the sharp rebuke of his unruly foreign minister, Stalin explained that although he was no scientist himself and had absolutely no knowledge of physics, he was not prepared to make light of Conant’s work. He then addressed the issue of the bomb for the first time. He praised Conant and his fellow atomic scientists for their achievement in creating the weapon that had brought the war to a close. They had rendered “a great service,” he continued in his hoarse voice. “We must now work together to see that this great invention is used for peaceful ends.” On that solemn note, he raised his glass in honor of the quiet, silver-haired American chemist. “Here’s to Professor Conant.”

Molotov, whose expression never altered, stood in grim silence. No one dared look in his direction. In the Politburo, survival depended on accurately reading and responding to the generalissimo’s moods, and anyone who earned his displeasure could expect there to be consequences. After an awkward pause, Conant stood. Holding his glass aloft, he thanked Stalin for his kind statement, and gamely acknowledged Molotov’s “humorous remarks,” though in truth he was rather floored by his cavalier attitude. Adding that he felt sufficiently emboldened by their sentiments, and by the “molecular energy of the excellent wine,” he offered a toast of his own, addressed to his Russian counterparts at the table. “I have no atomic energy in my pocket,” he began a bit sheepishly. “But I can say that the scientists of Russia and those of the other countries represented here tonight worked together to win a common victory. I trust they may cooperate equally effectively in the tasks of peace which lie ahead.”

After the coffee was served, and Conant rose to leave, Stalin detained him for a moment. The Soviet leader was much shorter and broader in person than Conant had imagined: not more than five foot four inches tall, he resembled “a shrewd but kindly and humble old peasant.” Speaking through an interpreter, Stalin repeated his earlier congratulations and again expressed his hope that the bomb could be used only for peaceful purposes and not for war. Then, referring to Conant’s generous toast, he added quietly, “Those were fine words, but were they sincere?”

Later, a few of the Americans and British gathered at Spaso House, the grand neoclassical manor that served as the US embassy, to share their impressions of the astonishing moment when history appeared to have suddenly changed course. Stalin had publicly humiliated his longest-serving deputy at a state dinner, signaling a decisive—if rather impulsive—change in attitude. While the generalissimo could be capricious, he knew what he was doing. Whether his displeasure with Molotov was genuine or staged was hard to tell. But the significance of the moment was not lost on anyone. The sixty-six-year-old Soviet despot, the most powerful and dangerous postwar ruler, was finally ready to incorporate nuclear weapons into his worldview. “There in the banquet hall of the Kremlin, we saw Stalin abruptly change Soviet policy,” recalled Charles Bohlen, a State Department aide and subsequent ambassador to Russia. “From that moment on, the Soviets gave the atomic bomb the serious consideration it deserved.”

It was the moment they had all “pinned their hopes” on—a sign that the Russians were prepared to cooperate. Stalin’s remarks indicated a willingness to work with the United States and Britain to control atomic energy and promote peace through international agreement. The Soviet experts in both delegations fairly hummed with excitement as they analyzed the various interpretations and implications of what had happened. Byrnes saw it as a cause for optimism. He immediately began making plans for the British-American—and now Soviet—resolution calling for the creation of an Atomic Energy Commission to be presented at the upcoming meeting of the United Nations General Assembly in London in January. He would even make arrangements, on his return to Washington, to make a nationwide radio broadcast reporting on the success of his trip.

Conant was not as quick to celebrate. Even in the convivial atmosphere that prevailed by the end of the long boozy evening, he had picked up on some troubling undercurrents. When they had finished dinner, they were escorted from the banquet hall to another room to watch a short film. It was purportedly about the war with Japan, but focused exclusively on the Soviet contribution to victory, even though the Red Army did not join the battle until August 9, 1945, the same day the second atomic bomb laid waste to Nagasaki. There was no hint that the United States and Britain had played any role except for a brief mention of Pearl Harbor and, in the closing minutes, a fleeting glimpse of a Japanese and a Russian general signing a treaty aboard the US battleship Missouri. Almost as an afterthought, an image of General Douglas MacArthur flashed by seconds before the end of the film. Irritated, Conant dismissed it as pure propaganda.

When the lights went up, he observed that many members of the American and British delegations were also indignant. Afterward, he could not help wondering at the Soviet’s motive in showing them such a “crass nationalistic movie.” Was it intended as an “intentional insult”? If so, what were the Russians playing at? “And no one, literally no one, is on a basis with Russian officialdom to say, ‘That was a bit thick, you know,’?” he noted in his diary, adding, “This little episode shows a lot.”

Equally disquieting was the Soviets’ refusal to grant them permission to make Stalin’s tribute to Conant and the atomic scientists public. It was a matter of protocol: what was said in the Kremlin, stayed in the Kremlin. Stalin’s recognition of America’s technical prowess could not be reported to the world. Despite all the talk of friendship between their two countries, the Iron Curtain was as tightly shut as ever. At the time, Conant was chiefly annoyed by the fact that there seemed to be no channel by which they could communicate their frustration to their hosts. Someone cynically suggested the best way to get word out would be to write down a list of their complaints and toss it in the wastebasket—it was certain that the next morning their message would be read in Molotov’s office in the Kremlin.

Despite all the “unfavorable evidence” he accumulated during his eleven days in Moscow, Conant remained convinced that the Russians would eventually see reason. Logic dictated that continuing their wartime alliance was the best way to proceed in the interdependent postwar years. If they did not act together to stop the manufacture of atomic bombs before it became widespread, the means of atomic destruction could find its way into the hands of an unexpected and reckless enemy.

In a speech he gave in late November, which was reprinted in the Boston Globe shortly before he departed for Moscow, Conant had predicted the Russians would soon get the bomb, giving a rough forecast of between five and fifteen years. He cautioned that the time estimate meant little, as the United States’ monopoly on this power was only temporary. There was “time, but not too much time” to evolve a plan for the exchange of scientific knowledge and the creation of an international inspection system. Without inspection there was no way to ensure their protection. Without it no one was safe. Conant startled his audience with this ominous injunction: “There is no defense against a surprise attack with atomic bombs.”

One thing has been as clear as daylight to me ever since I first became convinced of the reality of the atomic bomb; namely, that a secret armaments race in respect to this weapon must at all costs be avoided. If a situation were to develop where two great powers had stacks of bombs but neither was sure of the exact status of the other, the possibility of a devastating surprise attack by the one upon the other would poison all our thinking. Like two gunmen with itchy trigger fingers, it would only be a question of who fired first. Under such circumstances, the United States might be the loser.

Conant’s estimate was slightly off. Exactly four years and one month after Hiroshima, the Soviet Union would explode an atomic bomb, and two countries would be locked in a cold war struggle.

Years later, looking back on that extraordinary Christmas Eve in Moscow, Conant found it hard to believe that as 1945 came to a close, he could have had such faith in the future. He had hoped that the difficulties would disappear and they could proceed to work out a plan to preserve the peace instead of continually preparing for war. “My ascent into the golden clouds of irrational hope can only be explained by my honest appraisal of the worldwide catastrophic consequences of a failure to attain international control,” he later reflected. “Some scheme just had to work. And who is prepared to say my basic belief was wrong?”

He wrote those lines in 1969. Toiling over his memoir, safely ensconced in his wood-paneled study in Hanover, New Hampshire, he observed the perilous state of the world, “with American and Soviet aircraft and missiles poised to strike on a moment’s notice.” America was more vulnerable than ever before, and Conant had lost much of his old certainty, but none of the cold, clear-eyed Yankee pragmatism. A chemist, statesman, educator, and critic, he had had within his grasp all the elements to help forge the new atomic age. Supremely confident, he had acted upon his convictions to shape the kind of world he wanted to live in. He was, first and foremost, a defender of democracy. He had helped design and manufacture weapons of mass destruction in two world wars to protect liberty. He had fought for an open and fluid society, for a fairer system of higher education, for free discussion, a competitive spirit, and a courageous and responsible citizenry. He had occupied the presidency of Harvard as a bully pulpit, and had never hesitated to take daring stands on contentious issues, applying his reason, morals, and high ideals on matters of national import. As a “social inventor,” his term for the half century spent in public service, he had tried to find new formulas to keep alive the precarious American political experiment known as democracy.

As a war scientist, however, he knew he had much to answer for. Atomic energy’s “potentialities for destruction” were so awesome as to far outweigh any possible gains that might accrue from America’s technical triumph in the summer of 1945. Writing as an old man, he acknowledged that these new weapons of aggression had added to the frightful insecurity of the world, and he did not think future generations would be inclined to thank him for it. Yet the nuclear standoff had continued for years—no mean accomplishment given the number and variety of armed conflicts—which suggested that the stakes had become too high and the risks too great. Perhaps there might still be time to moderate the vicious arms race, though that remained for history to decide. “The verdict of history,” he wrote, “has not yet been given.”

About The Author

Photo Credit:

Jennet Conant is the author of Man of the Hour: James B. Conant, Warrior Scientist, and the New York Times bestsellers The Irregulars: Roald Dahl and the British Spy Ring in Wartime Washington and Tuxedo Park: A Wall Street Tycoon and the Secret Palace of Science That Changed the Course of World War II. She has written for Vanity Fair, Esquire, GQ, Newsweek, and The New York Times. She lives in New York City and Sag Harbor, New York.

Product Details

  • Publisher: Simon & Schuster (September 25, 2018)
  • Length: 608 pages
  • ISBN13: 9781476730912

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Raves and Reviews

“Gripping . . . an outstanding portrait of a technocrat, at work and at home.”

– Wall Street Journal

“A most serious work, well written and evocative of an era when the American foreign establishment exuded gravitas. . . . [a] new, relentless and personally invested account.”

– The New York Times Book Review

“This is biography and history at its best. The story of James Conant provides the perfect channel to engage our interest as we journey together through the major turning points of the 20th century. An intimate, sometimes heartbreaking portrait of Conant’s personal life is seamlessly linked to the great public achievements of his remarkable public career.”

– Doris Kearns Goodwin, Pulitzer Prize-winning author of Team of Rivals and The Bully Pulpit

A masterly account . . . a perceptive portrayal of a major player in world events throughout the mid-20th century.”

– Publishers Weekly

“[James B. Conant] is well-served by the 500 pages of his granddaughter's intensely researched, insightful, and rarely dull biography. Conant deserves a place among the traditional "wise men" (Acheson, Harriman et al.), an elite group of white, male, East Coast advisers, all pragmatic, realistic, and nonideological, who guided presidential policy from World War II through the end of the Cold War. This book gives him that place.”

– Kirkus Reviews

“Conant has written a thoughtful, complete biography of her grandfather, the influential scientist James B. Conant. . . . This extensive portrait of a contemporary of Winston Churchill, Robert Oppenheimer, and other key figures will appeal to anyone interested in the interplay of 20th-century science, academia, politics, and international affairs.”

– Library Journal

“No one is better suited to write a biography of James Conant, one of America’s historically most important national science advisers, than his talented granddaughter Jennet Conant. She’s made an outstanding and definitive work of it, one that illuminates the whole World War II and postwar eras.”

– Richard Rhodes, Pulitzer Prize-winning author of The Making of the Atomic Bomb

“From transforming Harvard to overseeing the construction of the atom bomb, James Conant was one of the most influential Americans of his time. Jennet Conant reveals his wisdom and explores his moral ambiguities with the grace of a bestselling author and the insights of a granddaughter.”

– Walter Isaacson, author of Leonardo da Vinci and The Wise Men

“James Bryant Conant did more to shape the world than all but a few presidents—developing the first WMD as a young chemist, running the Manhattan Project, governing post-war Germany and inventing the American meritocracy. Now his granddaughter, Jennet Conant, an esteemed historian, has brought his story brilliantly alive. This book is destined to be a biographical classic.”

– Jonathan Alter, author of The Defining Moment: FDR's Hundred Days and the Triumph of Hope

“A fresh take on [James B. Conant’s] life . . . Jennet Conant is a fine writer, and her biography emerges at a salutary moment. The story of James Conant's attempts to create a re-intellectualized US government and a better-educated public, and his vision of a shaping role for the United States in an ever-changing world, are important reminders in an age of devalued expertise, educational crises and turbulent governance.”


"[A] magisterial biography of one of the 20th century’s most influential men...she brings to her task the same objectivity, thoroughness and interest that her grandfather brought to his. Insightful and rich in detail, this book is a fitting tribute to a remarkable man."

– Bookpage

"Conant reconstructs her grandfather’s life through family diary entries, government documents, and newspaper articles, adding both intimacy and weight to the chronicle of a man seeking greatness."

– Santa Fe New Mexican

"An engrossing, nuanced portrait of a complex and enormously influential man."


"The point is that all these issues Conant and those of his time were grappling with — social mobility, college access, distorted facts, football, mental health, the atom bomb, Harvard alumni being worried about the state of the nation — are still with us, almost a century later."

– Newsmax

"Jennet Conant’s capable, informative portrait should be included in collections about the history of American science."

– Booklist

“Mr. Conant’s was a life of significant achievements. He brought a flinty New England competence to everything he tackled. His granddaughter, a New York Times best-selling author, brings comparable skill to the potentially tricky task of recounting that life. . . . an honest and balanced examination.”

– East Hampton Star

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