In 1945, Harry Truman ordered the first atomic bombing of another country; today, Barack Obama reserves the right to mount the world's next nuclear strike -- as have all American presidents since Truman. It is very odd that senior U.S. foreign policy officials, who have devoted most of the past seven decades to trying to control the spread of nuclear weapons, still want Washington to be able to use them first in a pinch. Even President Obama, a supporter of the abolition of all nuclear weapons, wants to be able to fire the first nuclear shot. No wonder North Korea, Iran, and others view efforts to get them to renounce their proliferation programs with much skepticism.
To be sure, the American ardor for atomic weapons has cooled since the famous Fortune magazine survey of December 1945, in which 22 percent of the public expressed the view that far more than "just" two nukes should have been dropped on Japan. Yet even as enthusiasm for inflicting massive destruction on others waned, there was still considerable fascination with these weapons in government and the military. Indeed, the idea of waging preventive nuclear war on Soviet Russia or communist China -- that is, hitting them before they had nukes of their own -- was closely considered for years, finally being rejected by Dwight Eisenhower in 1954.
This was the same year, however, that he articulated a doctrine of "massive retaliation" for any sort of act of aggression. Thus an incursion by some aggressor's conventional forces was now theoretically subject to a nuclear riposte. The idea was that this threat would keep the peace around the world. It didn't. Instead, a spate of irregular wars and acts of terrorism arose and, as Thomas Schelling put it in his classic Arms and Influence, the massive retaliation policy "was in decline almost from its enunciation."
Still, a version of massive retaliation lived on into the 1960s in the minds of NATO strategists who were concerned that Russian numerical superiority in tanks and warplanes was too great to match. And even after Western forces were beefed up, making conventional defense possible, the nuclear option was kept on the table in the form of an attractive euphemism, "flexible response." This meant that NATO would try to defend without resort to nukes, but would use them if it had to. Every "Reforger" exercise that began with conventional defense ended with the call for nuclear strikes.
Even as the Cold War was winding down and the Red Army was crumbling, the United States and its NATO allies grimly held on to the option of nuclear first use. Now it was only thought of as a last resort, but it was still on the books. And it remains a policy alternative today for NATO, though the current U.S. nuclear posture limits the right to first use by targeting only those nations who have not signed on or adhered to the various strictures imposed by the Nonproliferation Treaty -- which still leaves considerable room for first use.