One of the issues that spurred our war of choice in Iraq was the false insistence by the criminal Bush administration that Saddam Hussein had weapons of mass destruction, specifically nuclear weapons. The premise was that he might fly a drone (nutty) or worse give one of his precious nukes to a terrorist group who would then try to smuggle it into the United States.
I am probably dating myself with this, but back when I was a kid one of the things that was almost an article of faith with my friends and I was the prospect of an nuclear war of some kind between the United States and the Soviet Union. It was not a daily worry but it was always there in the back of our heads. It led to a lot of blue sky talking about post apocalyptic survival (and the realization that Michigan had 300 primary targets and no one was likely to survive in the state if the worst happened).
Luckily the Cold War ended and the chance of world wide nuclear holocaust receded. However that dread is a part of many peoples childhood and still influences their thinking. While there is a much lower chance of a major nuclear war, there seems to be a higher chance of a single city being destroyed by a nuclear weapon.