At the end of WWII, two events of enormous importance occurred that continue to frame our choices about peace and security to these days: the signing of the UN Charter in San Francisco, California, on 26 June 1945, and the first explosion of a nuclear device in Alamogordo, New Mexico, on 16 July 1945. These were like twin events; they took place within only 20 days of each other and within a radius of only about 900 miles (or 1,500 km) within the same country, the United States, the country that would dominate world politics to this day.

By the time the UN Charter came into effect on 24 October 1945 when the first 29 member states had ratified it, the first two nuclear bombs with the bizarrely cute-sounding names of Little Boy and Fat Man had killed about a quarter of a million people in Hiroshima and Nagasaki on 6 and 9 August 1945, almost all civilians. Never in human history had such a far-reaching international agreement curtailed the use of any military force as drastically as the UN Charter. And never before in human history had single weapon killed so many people in a single firestorm. Global peace became cornered between these two extremes – to these days.

Efforts to create collective security systems or to build ever more powerful weapons in the hope that this would protect from attacks and wars are nothing new in human history. Nonetheless, the global impact of both, the UN Charter and the nuclear bomb, marked a pivotal change for human society. The logic of peace and war changed after the summer of 1945. From then on, most political decisions had effects at an international level. With the UN Charter and the nuclear bomb, peace and security became irrevocably global.

The UN Charter and the nuclear bomb could hardly represent more opposite ways of wanting to maintain peace and security. While the UN Charter stands for efforts to maintain peace and security through a collective security system based on internationally accepted laws and norms, the nuclear bomb stands for keeping peace and security through the threat of force and mutually assured destruction (MAD).