Comment by tshaddox

When I think about nuclear war leading to human extinction, the first thing that comes to mind isn't any of those 3 mechanisms, but rather economic damage. Not economic damage as in "I lost my retirement investment," but as in "we can't produce enough food." I'd be worried about even much smaller and less deadly nuclear wars leading to massive civil unrest and breakdowns in large-scale social institutions and economies. Mass starvation would be the biggest killer. But I suppose that still wouldn't likely lead to absolute human extinction, but it could certainly lead to a future civilization that is largely unrecognizable to us humans accustomed to industrial or even agricultural societies.