There had not been a more perilous moment in the Cold War. 

Undaunted by the damp, dangerous night, Berliners gathered on the narrow side streets opening up onto Checkpoint Charlie. The next morning’s newspapers would estimate their numbers at about five hundred, a considerable crowd considering that they might have been witnesses to the first shots of a thermonuclear war.
 
After six days of escalating tensions, American and Soviet tanks were facing off just a stone’s throw from one another – ten on each side, with roughly two dozen more in nearby reserve.    Much has been written about the Cuban Missile Crisis that would come a year later, but the Berlin Crisis of 1961 was more decisive in shaping the Cold War – and was more perilous.
 
Reporting from the scene, CBS News reporter Daniel Schorr, with all the drama of his authoritative baritone, declared to his radio listeners, “The Cold War took on a new dimension tonight when American and Russian fighting men stood arrayed against each other for the first time in history. Until now, the East-West conflict had been waged through proxies – German and other. But tonight, the superpowers confronted each other in the form of ten low-slung Russian tanks facing American Patton tanks less than a hundred yards apart…”
 
General Lucius Clay, President Kennedy’s new special representative in Berlin, had set the confrontation in motion a week earlier over an issue most of his superiors in Washington did not consider a war-fighting matter. Breaking with established four-power procedures, East German border police had begun to demand that Allied civilians present their identity cards before driving into the Soviet zone of Berlin.
 
It was an arcane issue, but General Clay saw it as one of several he was ready to defend to win back some America’s eroded position in the divided city following President John F. Kennedy’s acquiescence to the construction of the Berlin Wall two-and-a-half months earlier.  From his own experience in leading the legendary Berlin airlift in 1948, which had broken a Soviet blockade of West Berlin, Clay was convinced that the Soviets would back down once they were convinced of U.S. resolve.
 
So Clay, to re-enforce the rights he felt the Kennedy administration had been ceding, ordered armed escorts to muscle civilian vehicles through. Soldiers carrying bayoneted rifles and backed by American tanks had flanked the vehicles as they wound their way through the checkpoint’s low, zigzag, red-and-white striped concrete barriers. At first, Clay’s approach was vindicated: the East German border guards had backed down each time Clay ran one of his convoys through the checkpoint.
 
After several days, however, Khrushchev ordered his troops to match U.S. firepower tank for tank and to be prepared to escalate further if necessary to stop the U.S. procedure.  In a curious if ultimately unsuccessful effort to preserve deniability, Khrushchev ordered that the Soviet tanks’ national markings be obscured and that their drivers wear unmarked black uniforms.
 
However, when the Soviet tanks rolled up to Checkpoint Charlie, they transformed a low-level border conflict with the East Germans into a war or nerves between the world’s two most powerful countries. U.S. and Soviet Commanders operating out of emergency operation centers on opposite sides of Berlin weighed their next moves as they anxiously awaited orders from President John F. Kennedy and Premier Nikita Khrushchev.
 
At about midnight in Berlin, or 6:00 p.m. in Washington, Kennedy reached Clay on a secure line in his map room in West Berlin.
 
“Hello, Mr. President,” Clay said loudly, abruptly ending the buzz behind him in the command center.
 
“How are things up there?” Kennedy asked in a voice designed to be cool and relaxed.
 
Everything was under control, Clay told him. “We have ten tanks at Checkpoint Charlie,” he said. “The Russians have ten tanks there, too, so now we’re equal.”
 
An aide then handed General Clay a note.
 
“Mr. President, I’ve got to change my figures. I’ve just been told that the Russians have twenty more tanks coming up, which would give them exactly the total number of tanks that we have in Berlin. So we’ll bring up our remaining twenty. Don’t worry about it, Mr. President. They’ve matched us tank for tank. This is further evidence to me that they don’t intend to do anything,” Clay said.
 
Kennedy could do his own math. Should the Soviets escalate their numbers further, Clay lacked the conventional capability to respond. Kennedy scanned the anxious faces of his advisers in the room. He propped up his feet up on the table, attempting to send a message of composure to men who feared matters were spinning out of control.
 
“Well that’s all right,” said the president to Clay, “Don’t lose your nerve.
 
“Mr. President,” responded Clay with characteristic candor, “we’re not worried about our nerves. We’re worrying about those of you people in Washington.”
 
Clay’s instincts proved correct. Even as the Soviets were escalating their tank presence, Clay received new instructions from Washington to retreat.  “In the nature of things,” Rusk wrote, “we had long since decided that entry into Berlin is not a vital interest which would warrant determined recourse to force to protect and sustain. Having for this reason acquiesced in the building of the wall we must recognize frankly among ourselves that we thus went a long way in accepting the fact that the Soviets could, in the case of East Berlin, as they have done previously in other areas under their effective physical control, isolate their unwilling subjects.”
 
For General Clay, it was the most revealing message he had received revealing President Kennedy’s thinking in accepting the Berlin Wall.
 
What Clay would never know was that Kennedy was so unnerved by the Checkpoint Charlie showdown that he had dispatched his brother Robert Kennedy, the attorney general, to solve the crisis with his regular interlocutor of the past six months, the Soviet spy Georgi Bolshakov. At the same time, he was working a second, more traditional channel through his ambassador in Moscow.
 
On the morning after the Bolshakov meeting, the Soviets began to withdraw their tanks. Robert Kennedy would later say that his exchange with Bolshakov demonstrated that the Soviet spy “delivered effectively when it was a matter of importance.”
 
Though he didn’t record the details of their talks, from that point forwarded, the U.S. stopped its military escorts of civilians, and Clay no longer challenged East German authority at the border points.  Though it had been the U.S. side that had retreated on the principle, it would be Soviet tanks who would withdraw first at 10:30 a.m. on Saturday morning, October 28. Some of them were covered by flowers, garlands put on them that morning by members of the Freie Deutsche Jugend, the party’s youth organization.
 
After a half hour’s wait, the U.S. tanks pulled back as well.
 
With that, the Cold War’s most dangerous moment ended with a whimper. However, the aftershocks of Berlin would be dramatic and long lasting. They would shake the world a year later when the Soviets would try to install nuclear missiles in Cuba  — and they would shape the world for another three decades, until the Berlin Wall finally collapsed of its own weight in 1989.
 
Fred Kempe is president and CEO of the Atlantic Council. His latest book, Berlin 1961, was published May 10. This blog series originally published by Reuters.

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