I think that even if a ICBM could not make it far enough they could always outfit a nasa or russian rocket with a nuclear warhead that could make it.
I think it also depends on how far out you want to hit it the farther the better. But hitting it with a nuke like in the movies might not be the best
thing to do you could turn a asteriod from a single bullet into buckshot which could be worst. I think a stand off blast would be your best bet just
to change its course not to destroy it. Scientist have thought up some interesting ways to stop a asteriod but none of them are operational or even
close to being a option. a nuke is the only chance we would have if a asteriod was heading for earth.




