If Kennedy had assented to his generals’ constant pressure to invade Cuba, the higher-than-known Soviet troop numbers would likely have made the landing and ground war much more difficult to win. This, in turn, would have created even greater pressure on Kennedy to escalate in order to avoid a politically devastating defeat. Such escalation would have then probably driven the Cubans and Soviets to use some of these nuclear weapons against invading forces. According to Soviet archives, Khrushchev did not initially comprehend that this would cause the U.S. to escalate to general nuclear war.
“We don’t need to speculate what would have happened,” McNamara declared when he finally learned—in 1992—about the Soviet deployment of tactical nuclear weapons to Cuba. “It would have been an absolute disaster for the world.”
In the 55 years since the Cuban Missile Crisis, America’s technical capabilities to gather intelligence have improved breathtakingly. Still, it’s extremely difficult to know how foreign adversaries perceive their situation and calculate their moves, especially when key targets of intelligence do not reveal their inner thoughts in phone calls, texts, and emails that can be intercepted.
The U.S. and other governments know that North Korea has nuclear weapons that work. The number is uncertain; estimates run from 15 to 60. North Korea has tested a variety of missiles whose ranges extend from 50 to 8,000 miles. (Pyongyang, the capital of North Korea, is 120 miles from Seoul, the capital of South Korea. Washington is about 6,750 miles from Pyongyang.) The reliabilities of the various missile types, again, are uncertain. Outsiders, as well as Kim himself, cannot know whether nuclear warheads mounted on longer-range missiles would detonate as planned.
Similar uncertainties apply to the effectiveness of the ballistic missile defenses that the U.S. has deployed in Alaska to knock out North Korea’s long-range missiles. Such defenses have not been tested in wartime conditions. Last October, Trump told Fox News’s Sean Hannity, “We have missiles that can knock out a missile in the air 97 percent of the time.” Experts debunked this claim and the Pentagon did not defend it. But if the president believes it, or the North Koreans believe he believes it, then the risk of nuclear conflict could be greater than it should otherwise be. The president could be emboldened to strike North Korea, believing that missile defenses would limit North Korea’s retaliation. Kim could back down for the same reason, or, more likely, he could be motivated to expand his nuclear arsenal and delivery options so that he would have more confidence in being able to retaliate against Trump.
Prior to talk of a summit, the Trump administration had been contemplating and preparing for strikes against North Korean military facilities if North Korea were to conduct another test of an ICBM or a nuclear weapon. The idea, according to credible reports, was not to undertake or signal a war to remove the North Korean regime, but rather to demonstrate America’s seriousness and capacity to compel Kim to stop such provocations. If the North Koreans respond to the summit’s cancelation by flexing their nuclear or missile capabilities, the White House will feel pressed to push back. Advocates of such military action seem to presume that the North Korean leadership and all the officers dispersed under their command would correctly interpret the limited threat that Trump would be signaling and would not respond militarily in ways that would compel Trump to one-up the North.