Nuclear non-proliferation is the effort to eliminate the spread of nuclear weapon technology, and to reduce existing stockpiles of nuclear weapons. Nuclear-weapon nations and their allies don’t want any other nations or entities to get the technology, and those threatened by or otherwise hostile to these nations (or any other nations) often want to have it. Meanwhile, peaceful people across the world want no one to have nuclear weapons. To reach their goal, people working for non-proliferation must secure and monitor existing nuclear weapons and weapon material, they must monitor facilities conceivably able to produce weapon material and minimize the construction of such facilities, and they must perform political gymnastics to minimize the allure of nuclear weapons to the world.