Although much less probable than during the Cold War and much exaggerated as a scenario, a nuclear war could still be a threat to humanity in the near future. There are currently 9 countries having in their possession nuclear weapons: the United States, Russia, France, China, United Kingdom, India, Pakistan, North Korea and Israel. Iran might soon become the tenth. The more countries being in possession of nuclear weapons, the more probable would a catastrophic outcome such as a nuclear war become reality. But fortunately, for now, this probability is quite small.