Despite the end of the Cold War, during which their possession was justified as a deterrent, massive stockpiles of nuclear weapons and nuclear materials remain. Including those in storage there are some 30,000 nuclear warheads worldwide today.
The United States has some 7,000 active nuclear weapons, Russia over 8,000, France some 450, China some 400, and Britain 185 nuclear weapons.
India and Pakistan have both tested nuclear weapons and declared themselves nuclear weapons states in May 1998. A war on the subcontinent is currently the likeliest to lead to the use of nuclear weapons. Israel is believed to have about 200 nuclear weapons. North Korea and Iran have made clear their intention to attain nuclear weapons. More than 40 states can develop nuclear weapons because they have nuclear reactors.
In these increasing arsenals of nuclear weapons, up to 5,000 are kept on hair-trigger alert, ready to be launched at short notice. This greatly increases the possibility of a nuclear accident from false alarm or unauthorised access.