The last time the asteroids came to earth with the one mile dia (est) rock, it ended the ice age; 1000 years later the next one mile dia (est) struck it brought on the Younger Dryas - colder than the ice age temps.
Search for “the Carolina Bays” and read “Magicians of the Gods”.
These rocks are thew remnants of a broken up comet. Usually we pass thru the part of the torus with the small stuff which make a nice shower. But once in a while we pass thru where the big stuff lives and they are civilization-enders and real climate changers.
No, nukes only make more pieces which hit more targets - all you an do is find a successful way to move the rock so it does not cross earth’s orbit.This presupposes you have already not only detected the rock, but calculated its actual orbit and crossing time - one miscalculation and the jig is up.
Yea but I saw a movie about it;)