@SaareMartha @peterbutler @JessTheUnstill There are fewer than 10,000 nuclear weapons on the planet, down from a peak of over 50,000 in the 80s. And they're smaller than most people realize—the really big H-bombs were militarily useless so they were retired first.
We *could* build a bomb big enough to do real damage—designs for such go back to the late 1950s—but such doomsday weapons would be immobile and easily disrupted by an attacker, which is why second strike forces are submarine-launched.