Forty years ago this month President John F. Kennedy sat in the Cabinet Room with his top national-security aides and discussed the idea of launching a nuclear first strike against the Soviet Union. This was no theoretical chat. Soviet Premier Nikita Khrushchev was threatening to take over West Berlin. War seemed not merely possible but likely. The Joint Chiefs of Staff had determined that the United States and its European allies could not defend West Berlin with conventional weapons alone. That left nuclear war as the alternative to surrender. During the summer of 1961 a small group of officials in the Pentagon and the White House had worked out a plan for a first strike that would virtually wipe out the Soviets' nuclear arsenal, minimizing the chance of retaliation. The plan was concrete and highly detailed. It spelled out what flight paths the U.S. bombers should take, at what altitudes they should fly, and which targets they should hit with how many of what kinds of nuclear bombs. And it concluded that the mission was feasible—that there was a "fair probability" of success.

The existence of this plan was first revealed in a chapter of my book, The Wizards of Armageddon (1983), but that account relied almost entirely on interviews with former officials. Save for one or two highly circumstantial memoranda, whatever documents may have existed about the plan were locked in the vaults. The first-strike plan was mentioned in a couple of subsequent histories, but it was dismissed as a "back-of-the-envelope" calculation that Kennedy probably never saw.

With the fortieth anniversary of the Berlin crisis approaching, I decided to see if any documents had surfaced in the two decades since my book was published. They had. The first-strike plan, it turns out, was put forth in a coldly analytical thirty-three-page memorandum to General Maxwell Taylor, Kennedy's special military adviser. (It was discovered among Taylor's papers at the National Archives and declassified through a Freedom of Information Act request by the National Security Archive, a private research organization.) Other documents, including many declassified over the past few years by the Kennedy Library, in Boston, show that the memo was passed on to the Joint Chiefs of Staff, was discussed at meetings of the National Security Council, and was read—and seriously contemplated—by President Kennedy. The documents, never before described, reveal a new chapter of history.

A dozen years after the Berlin Wall came down and the Cold War ended, it is hard to imagine the fear and passion that once surrounded the very word "Berlin." The Berlin crisis of 1961 may be the forgotten crisis in the annals of superpower confrontation—obscured by the Cuban missile crisis, which followed it a year later. Even most citizens who lived through the event remember little about it. Yet the conflict over Berlin brought America and the Soviet Union no less close to war than did the high drama of those "thirteen days" over Cuba. Berlin was the centerpiece of struggle throughout the Cold War. It was where World War II ended in Europe, the Allied armies slamming into one another as they occupied Nazi Germany—the United States, Britain, and France from the west, the Soviet Union from the east, carving out the separate zones of West and East Berlin. Soon afterward Germany itself split into West and East, and the border between the two hardened into the dividing line between Soviet-controlled Eastern Europe and free, capitalist Western Europe. West Berlin became an anomaly—a tiny landlocked island, claimed and protected by the Western powers but stuck a hundred miles inside Eastern territory. In 1948 Stalin imposed a blockade, cutting Berlin off from its Western suppliers. The United States responded with an airlift, keeping the zone alive for more than 300 days before access was restored. Ten years later Khrushchev threatened to put West Berlin under East German sovereignty by force, but he backed off after meeting with President Dwight Eisenhower at a Camp David summit. To every Western leader West Berlin shone as a beacon of freedom and a potent symbol of the U.S. commitment to resist Soviet aggression. To succumb to Soviet pressure on Berlin would be to destroy America's credibility worldwide. On this point there were no hawks and doves: all saw it as a fundamental truth.

In 1960, when Jack Kennedy was running for President, he predicted that Berlin would be a "test of our nerve and our will." In January of 1961, two weeks before Kennedy's inauguration, Khrushchev renewed his threat, demanding that the Western powers sever ties to Berlin, and vowing "resolute measures" if they resisted. The young President faced this test of nerve from the moment he took office.

On April 25 Kennedy sent a memo to his Secretary of Defense, Robert McNamara, requesting a report on the status of military planning for a possible crisis over Berlin. McNamara replied on May 5: NATO could not defend West Berlin with conventional weapons alone. Even an airlift "would not succeed in reopening and maintaining air access in the face of determined Soviet opposition." McNamara made plans to reinforce U.S. troops and supplies in West Germany.

In June, Kennedy flew to Vienna to meet with Khrushchev. He hoped the summit would calm tensions, but they only worsened. Kennedy ended the summit famously grumbling, "It will be a cold winter."

Around the same time, Dean Acheson, who had helped to create the NATO military alliance while he was Secretary of State, under Harry Truman, wrote Kennedy a long memo on Berlin, which the President circulated widely. Acheson endorsed McNamara's plan to upgrade conventional forces, but warned that it would do no good unless the Soviets were convinced that any move against Berlin would trigger all-out war between the United States and the USSR—which, by definition in those days, meant nuclear war.

On July 7 Henry Kissinger, then a professor at Harvard and a part-time consultant to the National Security Council, wrote a memo to McGeorge Bundy, Kennedy's national-security adviser, titled "General War Aspect of Berlin Contingency Planning." Kissinger wrote,
The Acheson report correctly points out that the President must make an early decision about his willingness to risk nuclear war over Berlin ... [However,] before he makes the decision he has to know what is meant by nuclear war. It would therefore seem to me essential that the nature of our nuclear options be defined now.
U.S. military policy at the time called for "massive retaliation" in the event of general war—shooting off all our nuclear weapons against every target in the Soviet Union, China, and parts of Eastern Europe, no matter how limited the cause of the war might be. This single integrated operational plan—or SIOP, as the military called it—was so tightly woven into the logistics and training of the U.S. Strategic Air Command that it would be impossible to launch a smaller-scale nuclear attack even if the President wanted to do so. The problem with this SIOP, in the view of many defense analysts, was that if the United States unleashed the full attack against the USSR, the Soviets would initiate a retaliatory strike once they saw the attack coming, ultimately killing tens of millions of Americans. So what to do? Many feared that a President in crisis would face the choice of "suicide or surrender," "holocaust or humiliation."

In his memo to Bundy, Kissinger said that the Pentagon "should be asked to submit a plan for graduated nuclear response"—using nuclear weapons in some limited way that might avoid both horns of the dilemma. He added, "I have discussed the problem with both Carl Kaysen and Henry Rowen."

Kaysen was another Harvard professor, on leave to serve as a special assistant to Bundy. Rowen was a nuclear strategist from the Rand Corporation, now serving as a deputy assistant secretary of defense under McNamara. Both are minor characters at best in the chronicles of history, but they took charge of organizing the first-strike plan.

The plan took shape at the start of the summer, when a Pentagon consultant named William W. Kaufmann, another Rand strategist, learned some startling news about the Soviet nuclear arsenal. Since the year before, the supersecret Discoverer spy satellites had been taking thousands of photographs over the Soviet Union. Kennedy had come into office railing about a "missile gap" that was giving the Soviets a dangerous edge over the West. The Discoverer photos revealed, however, that the gap went the other way: the United States was far ahead. The Soviets had no more than eight intercontinental ballistic missiles (ICBMs). Their bombers sat out on open runways. Their air-defense batteries were virtually worthless.

Back at Rand, Kaufmann had pondered in theory the problem that Kennedy now faced in fact—how to use nuclear weapons in a nonsuicidal way if, say, the Soviets invaded Western Europe and we could not stop them with conventional forces. He had proposed the possibility of launching a disarming nuclear first strike against the Soviets' missile sites and bomber bases, holding in reserve many more nuclear weapons, and threatening to fire them at Soviet cities if the Soviet Union did not pull back. Some colleagues had told Kaufmann that his plan was unrealistic. But now he saw a way it might work. If the Soviets had only a few nuclear weapons and terrible air defenses, maybe the United States could knock out the whole Soviet nuclear arsenal in a very small sneak attack.

Rowen had been a close friend of Kaufmann's at Rand. Kaufmann told him about the implications of the Discoverer data. Kaufmann says that Rowen took him to meet Kaysen, who in turn informed Kissinger and Bundy of the findings.

On July 7, the same day that Kissinger wrote his memo to Bundy about a "graduated" use of nuclear weapons, Bundy passed the suggestion on to Kennedy, saying that he, Kissinger, and Kaysen "all agree that the current strategic war plan is dangerously rigid and ... may leave you very little choice as to how you face the moment of thermonuclear truth."

Six days later Kennedy held an NSC meeting on Berlin. Among the items on the agenda: "steps to prepare war plans which would permit the discriminating use of nuclear weapons in Central Europe and ... against the USSR."

By July 21 the issue had percolated through the upper echelons of the national-security bureaucracy. An NSC memo, marked up by Bundy, stated, "The whole question of military courses of action in the event access is blocked needs to be studied more effectively." One issue, which the memo said the President needed to consider, was "nuclear war: how to make it more flexible."

On July 25 Kennedy went on national television to outline his concerns about a possible crisis over Berlin, and to announce an increase in the defense budget for more troops and ammunition. In a memo to McNamara he called for greater attention to civil defense and fallout shelters.

On August 13, before dawn, East German soldiers pulled construction vehicles up to the border between East and West Berlin, and started to erect the Berlin Wall. At first Kennedy saw this step as the end of the crisis. Khrushchev had been so determined to block access to West Berlin in part because more than 10,000 East German citizens a month were crossing into West Berlin and emigrating from there to West Germany. But the wall unleashed loud protests from European diplomats. The crisis continued.

Kaysen and Rowen finished their first-strike study a few weeks later. On September 5 Kaysen, who had taken over the drafting of the plan, sent General Taylor the resulting thirty-three-page memo, titled "Strategic Air Planning and Berlin." It included a very detailed description of the existing U.S. nuclear-war plan. SIOP-62, as the plan was known, called for sending in the full arsenal of the Strategic Air Command—2,258 missiles and bombers carrying a total of 3,423 nuclear weapons—against 1,077 "military and urban-industrial targets" throughout the "Sino-Soviet Bloc." Kaysen reported that if the SIOP were executed, the attack would kill 54 percent of the USSR's population and destroy 82 percent of its buildings. Kaysen asked,
Is this really an appropriate next step after the repulse of a three-division attack across the zonal border between East and West Germany? Will the President be ready to take it? ... Soviet retaliation is inevitable; and most probably, it will be directed against our cities and those of our European allies.

What is required in these circumstances is something quite different. We should be prepared to initiate general war by our own first strike, but one planned for this occasion, rather than planned to implement a strategy of massive retaliation. We should seek the smallest possible list of targets, focussing on the long-range striking capacity of the Soviets, and avoiding, as much as possible, casualties and damage in Soviet civil society. We should maintain in reserve a considerable fraction of our own strategic striking power; this will deter the Soviets from using their surviving forces against our cities; our efforts to minimize Soviet civilian damage will also make such abstention more attractive to them, as well as minimizing the force of the irrational urge for revenge.
It was a plan straight out of the Rand Corporation, straight out of Dr. Strangelove (except that Stanley Kubrick didn't make that dark satire for another two years). It was a plan to wage rational nuclear war.

Kaysen then laid out the details of the plan. "There are three types of targets which it seems essential to destroy in the first wave of an attack," he wrote. These were the forty-six home bases for Soviet nuclear bombers, the bombers' twenty-six staging bases, and the up to eight ICBM sites (with two "aiming points" for each site, or sixteen targets in all), for a total of eighty-eight targets—or, in the military parlance, DGZs (for "designated ground zeros").

"If we destroy a total of 88 DGZ's," the memo continued, "we will have eliminated or paralyzed the nuclear threat to the United States sufficiently to permit follow-on attacks for mop-up purposes or for the elimination of other targets." Given that some of these DGZs were within twenty minutes' flying time of one another—meaning that several of SAC's bombers could hit one set of targets and then move on to hit another—Kaysen estimated that the first strike could be carried out by a mere fifty-five bombers. He calculated that almost none of the planes would be shot down, and cited a CIA intelligence estimate of July 11 stating that the Soviet air-defense system "would lose most of its effectiveness" if bombers flew in at low altitudes.

Kaysen acknowledged the need for more "detailed operational studies and exercises" to test these assumptions. "But," he added, "there are numerous reasons for believing that the assumptions are reasonable, that we have the wherewithal to execute the raid, and that, while a wide range of outcomes is possible, we have a fair probability of achieving a substantial measure of success."

The calculations foretold a fairly clean attack, by the standards of nuclear-war planning. "Given the locations of the targets," Kaysen wrote, "[Soviet] mortalities from the initial raid might be less than 1,000,000 and probably not much more than 500,000." The implication seems to have been that a million casualties would not be terrible enough to incite in the Soviet leadership an "irrational urge for revenge." However, Kaysen also noted that these numbers assumed "no gross errors in the bombing." Furthermore, if some Soviet weapons survived the attack and the Soviet leaders retaliated, quite a bit of damage could be done to the United States. Again, the range of possibilities was very wide—depending on whether the Soviet weapons were aimed at cities or at military targets, whether they were designed to explode in the air or on the ground (the latter would produce more radioactive fallout), and whether or not American citizens hid in fallout shelters. Kaysen provided two charts, labeled "Prompt Deaths from Alternative Bombing Attacks (Deaths Due to Blast and Prompt Radiation)" and "Deaths from Alternative Attacks on U.S. Cities (Blast and Fallout, All Weapons Ground Burst)." Depending on the assumptions, American fatalities would range from negligible in the best case to 75 percent of the population in the worst case. "In thermonuclear warfare," Kaysen wrote, "people are easy to kill."

However, he emphasized, "The choice may not be between 'go' and 'no-go'; it may be between 'go' and SIOP-62. Compared with SIOP-62, the small-scale, minimum-warning attack—coupled with carefully timed and executed follow-on raids—has distinct advantages."

Two weeks later, on September 19, Kennedy sent Taylor a list of questions to pass on to General Lyman Lemnitzer, the Chairman of the Joint Chiefs of Staff, and General Tommy Power, the commander-in-chief of SAC, to be discussed at a meeting that the four were scheduled to have the next day. The questions clearly indicate that Kennedy had read Kaysen's memo, or at least a very detailed summary of it.

"Berlin developments may confront us with a situation where we may desire to take the initiative in the escalation of conflict from the local to the general war level," the President wrote. Referring to SAC's existing nuclear-war plan, he asked,
Is it possible to get some alternatives into the plan? ... Is it now possible to exclude urban areas or governmental controls, or both, from attack? ... How would you plan an attack that would use a minimum-sized force against Soviet long-range striking power only? ... Would it be possible to achieve surprise with such a plan during a period of high tension? ... Would not an alternate first strike plan, even if only partially successful when implemented, leave us in a better position than we would be if we had to respond to an enemy first strike? ... Is this idea of a first strike against the Soviets' long-range striking power a feasible one?
Kennedy also posed questions about some risks that Kaysen had not considered, indicating that the President was doing his own thinking, and possibly developing his own skepticism, about the matter. "I am concerned over my ability to control our military effort once a war begins," he wrote.
I assume I can stop the strategic attack at any time, should I receive word the enemy has capitulated. Is this correct? ... Although one nuclear weapon will achieve the desired results, I understand that, to be assured of success, more than one weapon is programmed for each target. If the first weapon succeeds, can you prevent additional weapons from inflicting redundant destruction?
At the next day's meeting nobody addressed these questions. According to the minutes, General Power spent most of the time claiming that the Soviets had hidden away "many times more" missiles than the CIA's spy photos had indicated—a point that Lemnitzer and Taylor disputed. Power, a flamboyant commander who never warmed to the notion of "limited nuclear strikes," told the President that "the time of our greatest danger of a Soviet surprise attack is now" and advised that "if a general atomic war is inevitable, the U.S. should strike first."

Kennedy seems to have ignored this rant; he returned to his main concern—whether he could really launch a sneak attack without provoking catastrophic retaliation. He asked the generals "to come up with an answer to this question: how much information does the Soviet Union need, and how long do they need to launch their missiles?"

It is unclear whether the question was ever answered, but Kennedy remained interested in exploring a first-strike option. On October 10 he met with top officials and generals in the Cabinet Room to discuss contingency plans for Berlin. Prior to the meeting Assistant Secretary of Defense Paul Nitze, who was aware of the Kaysen-Rowen study, had drawn up—in consultation with the Joint Chiefs—a document titled "Preferred Sequence of Military Actions in a Berlin Conflict." The document laid out four scenarios in outline form.

I. If the Soviets interfered with access to Berlin, the Allies should send out a platoon.

II. If the Soviets persisted, the Allies should "mobilize and reinforce rapidly to improve capability for taking actions."

III. If the Soviets still didn't stop, the Allies "should take one or more of the following military courses of action:"
A. Naval blockade [target unspecified].

B. "Expanding non-nuclear air action" and "ground defensive strength."

C. "Expanding non-nuclear ground advance into [East German] territory, with strong air support." Here, though, Nitze noted, "This is a politically oriented military operation aiming to display to the Soviets the approaching danger of possibly irreversible escalation. Military overpowering of determined Soviet resistance is not feasible."
IV. "If, despite Allied use of substantial non-nuclear forces, the Soviets continue to encroach upon our vital interests, then the Allies should use nuclear weapons."

This could be done gradually, as follows:
A. "Selective nuclear attacks for the primary purpose of demonstrating the will to use nuclear weapons."

B. "Limited tactical employment of nuclear weapons" on the battlefield.

C. "General nuclear war."
During the meeting, according to Bundy's minutes, Kennedy asked "whether in fact there was much likelihood that IV. A. and B. could be undertaken without leading to IV. C."—in other words, whether nuclear weapons could be used in small doses without escalating to all-out nuclear war.

Nitze believed "that since IV. A. and B. would greatly increase the temptation to the Soviets to initiate a strategic strike of their own, it would be best for us, in moving toward the use of nuclear weapons, to consider most seriously the option of an initial strategic strike of our own"—in short, executing the Kaysen-Rowen plan. "With such a strike," Bundy wrote, summarizing Nitze's remarks, "we could in some real sense be victorious in the series of nuclear exchanges, while we might well lose if we allowed the Soviets to strike first."

McNamara, on the other hand, felt "that neither side could be sure of winning by striking first and that the consequences to both sides of a strategic exchange would be so devastating that both sides had a very high interest in avoiding such a result."

Secretary of State Dean Rusk, who had been left out of these contemplations until now, remarked that "the first side to use nuclear weapons will carry a very grave responsibility and endure heavy consequences before the rest of the world."

Bundy summed it up: "The division of opinion over Paragraph IV was not flatly resolved."

The controversy was taken up once more on October 20. In a memo about that day's upcoming meeting on Berlin, Bundy told Kennedy that the matter remained "unresolved," adding, "This issue, bluntly, is whether we can and should have nuclear strikes short of the massive strategic attack which is the current basic plan for general war ... again you may wish to press for continued analysis." Here Bundy wrote in by hand, "McNamara has just called to say they are not prepared on this for today."

Finally Kennedy decided to send his own message to Khrushchev—a warning. On October 21, on Kennedy's orders, Deputy Secretary of Defense Roswell Gilpatric gave a speech in Hot Springs, Virginia, that let everyone know for the first time—and let Khrushchev know we knew—that there was no missile gap. He revealed how many nuclear weapons we had, emphasized that the arsenal would be second to none even after a Soviet attack, and said, "The Iron Curtain is not so impenetrable as to force us to accept at face value the Kremlin's boasts." For years Khrushchev had bragged of a tremendous Soviet missile arsenal. He had based his diplomatic threats about Berlin on the assumption that the United States still believed the boast. Now he knew the game was over.

Gilpatric's speech came in the middle of the Communist Party Congress, so Khrushchev felt he had to respond. He proceeded with plans to detonate a thirty-megaton hydrogen bomb, the largest tested to date. The night after Gilpatric's speech, as the ranking U.S. diplomat drove to an opera in East Berlin, East German border guards blocked his way. Over the next few days the confrontation became tenser, climaxing on October 28, when thirty tanks from each side faced one another for sixteen hours at a range of a hundred yards. But the Gilpatric speech seems to have had its desired effect. After some back-channel diplomacy between Kennedy and Khrushchev, the crisis ended. For the next twenty-eight years Berlin would be a city divided by the physical barrier of the wall; but the Soviets would never again subject West Berlin to overt intimidation.

The crisis left two main legacies: First, it led directly to the Cuban missile crisis of October, 1962. After October of 1961 Khrushchev saw that he needed real military leverage if he was going to make another play for Berlin. Installing medium-range missiles in Cuba, within close range of U.S. targets, would have the same effect as a crash buildup of ICBMs. Khrushchev failed in Cuba and lost his job. His successors ordered the crash buildup, which helped to accelerate the nuclear arms race that would dominate international politics over the next quarter century.

Second, even as the Berlin crisis mounted, Robert McNamara ordered changes in the U.S. nuclear-war plan. The new version, called SIOP-63, and all the subsequent revisions, ensured that future Presidents, who might face their own "moment of thermonuclear truth," would have at least the appearance of "flexible options"—including variations on John F. Kennedy's first-strike plan.