Thank you.
The threat of proliferation of nuclear weapons to non-state actors, or nuclear materials, even if not in weapon form, has had the most sobering effect on the move towards stricter adherence to non-proliferation and disarmament. When Kissinger, Sam Nunn, and George Schultz made their statements about nuclear disarmament, that's one of the things they were particularly concerned about.
We're recognizing that the notion that we can have a stable international community in which some remain “have” states of nuclear weapons for a long time while others do not is not possible in a world in which nuclear material, nuclear know-how, is widely dispersed. Any emerging industrial country—Iran would be an example—that has some universities and a scientific community, plus access to nuclear materials, can gain access to nuclear weapons. They have particular relationships with non-state groups. That's the most sobering element of it.
By the way, placing small bombs in a whole bunch of airfields around Europe is probably not the best security move.