The rumor that raced through Washington last week of an atom bomb someplace in the city being readied for the next terrorist atrocity had a familiar ring to me.

In late July 1961, President Kennedy, just back from the grim Vienna summit with Khrushchev, asked me to dinner in Palm Beach. After daiquiris and Frank Sinatra records on the patio, his three guests and I gathered around the table for fish-in-a-bag, a White House recipe. Between lusty bites, Kennedy told the story of Khrushchev's anger over West Berlin, the island of freedom in the Soviet empire's East Germany. "We have a bustling communist enclave just four blocks from the White House," I noted, meaning the Soviet embassy. Kennedy paused, fork between plate and mouth, and said, "You know, they have an atom bomb on the third floor of the embassy." Aware of JFK's love of spy stories, I said something like, "Sure, why not?" (See the worst nuclear disasters of all time.)

No, Kennedy continued, it was his understanding that the Soviets had brought the components of an atomic device into the building in inspection-free diplomatic pouches and assembled it in the upstairs attic. "If things get too bad and war is inevitable," he said, "they will set it off and that's the end of the White House and the rest of the city." I laughed. Still suspending his bite of fish, Kennedy said, "That's what I'm told. Do you know something that I don't?" No sign of mirth. The conversation moved on.

Five years ago I was lecturing in Staunton, Va., and retold the story. In the question session, a man in the audience rose and said, "You may not believe that story about the bomb in the attic, but I do. I worked for 25 years at the Defense Intelligence Agency, and that was our understanding." And now I can hear Kennedy asking again, "Do you know something I don't?"

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