They laughed when I. I. Rabi got out of the car carrying an umbrella in July, 1945. It was midsummer in the desert of southern New Mexico and Rabi, dressed for the streets of New York, had brought an umbrella to the test of the world's first atomic bomb. But it soon started to rain. Rabi's friend J. Robert Oppenheimer was in a state until the weather cleared just about dawn and they set off the bomb that Rabi had refused to work on. He told his friend Robert he wanted no part in making a bomb as the culmination of three centuries of physics.
It wasn't just the rain Rabi got right that day; he guessed the bomb's yield--the equivalent of 20,000 tons of TNT. Oppenheimer was afraid it would only fizzle so Rabi, trying to be polite, picked the biggest number left in the pool. Two things Rabi saw that day he told people about until the end of his life. One was the transformation of Oppenheimer when the bomb went off--after all the pacing and chain-smoking, Oppenheimer looked, in his moment of triumph, like a prince of darkness. The other was that the future of mankind in a world with such weapons had already begun to look bleak to Isadore Isaac Rabi, the Nobel Prize-winning U.S. physicist who died at 89 last week. The first half of Rabi's life was physics; the second half was trying to decide how to deal with what physics had wrought.
The first approach--a plan for international control--was dreamed up in Rabi's Riverside Drive apartment near Columbia University in December, 1945. History calls it "The Baruch Plan," after Bernard Baruch, who presented it to the United Nations, but its authors were Rabi and Oppenheimer. A leading Russian physicist, Dmitri I. Skobelitsyn, came to see Rabi asking if the United States was serious. He pulled out newspaper clippings of blustering speeches by the Republican Sen. Robert Taft. Rabi told him to pay no attention, the plan was serious. "I was so proud of the United States for putting it forward," he said.
Rabi tried to persuade Oppenheimer to serve as Baruch's adviser but Oppenheimer didn't get along with Baruch and refused. When the plan reached the United Nations, it had just enough Baruch to put off the Soviets--the effort died.
When the Soviets detonated their first bomb in August, 1949, Rabi was a member of the General Advisory Committee to the Atomic Energy Commission, a group that Oppenheimer ran like a college seminar. The commission was beginning to feel political pressure for an all-out program to develop thermonuclear bombs to show the Soviets, and reassure the Americans, that we were still "ahead." Oppenheimer was asked to poll committee members.
At first Rabi thought a thermonuclear program made sense. He was thinking as a scientist, and the science was interesting. But then he began to think as a human being. "During the war I heard a lot of people say, 'Our next war will be with Russia,' Rabi told me. "I'd always say, 'Who'll rent us a battlefield?' " Gradually he realized that aircraft meant the whole planet might serve as battlefield. Now the military wanted a bomb a thousand times more powerful than those that destroyed Hiroshima and Nagasaki. Rabi the scientist quit caring whether a fusion bomb could be made to work; Rabi the man was against it. He joined his friend Enrico Fermi in writing a separate opinion on the H-bomb question for the AEC in October, 1949, calling the new weapon too powerful for any purpose but "genocide," and "necessarily an evil thing considered in any light." No piece of official U.S. paper about the bomb had ever said anything quite so flat-out before--and none has since. The military was furious and President Harry S. Truman eventually decided to build the H-bomb; Rabi's strong words were buried under "top secret" stamps for 25 years.
That was the real Rabi, a contradictory figure who refused to work on the first atomic bomb full-time but lent a hand whenever friend Oppenheimer asked, who spent the last 40 years of his life talking to all and sundry about dangers posed by nuclear weapons and then, not far short of the end, said he was taking "a vow of silence." Why a vow of silence?
"Because when people talk about these weapons long enough they get turned around," he said. "They start off scared of the weapons, but then they get scared of the Russians and decide to build more."
Even worse, people become morally obtuse. Rabi remembered the two government officials who came to see him in 1950, shortly after the Chinese army entered the Korean War. U.S. troops were in trouble; the officials wanted Rabi's professional opinion: Would it be feasible to use cobalt bombs to poison the Yangtze River? This did not strike Rabi as a fitting crown for three centuries of physics and he showed his visitors the door.