Apocalypse as in mundane real world or as mass spiritual catastrophe? If the former then what would apocalypse mean or entail anyway? So North Korea can hit the coast of California with nuclear war heads and the USA could retaliate probably decimating a few major North Korean cities. I doubt that China would retaliate by firing at the other major USA cities but if they do then it may escalate with various other major nations of the developing world taking shots. After a period of decimation when ceasefires are made, this still doesn't amount to an apocalypse as such. If anyone knows better then let me know. I mean, Hiroshima and Nagaski have their problems now sure but it's not like the entire Japanese population were poisoned by fall-out. To have a proper apocalypse, "salt bombs" would have to be used. This particular species of nuclear weapon lingers within the earth's atmosphere and is even more hazardous to populations on the receiving end however such "doomsday devices" are more sci-fi than reality.
If however you're talking super massive asteroid entering our system and able to bypass the protective gravitational fields of the planet Jupiter then yeah now you're talking. That would hasten massive super-volcanic activity creating decades of thick ash encapsulation of the earth itself. The Sun's rays wouldn't get through to us and a new ice age would commence. A new "snowball earth!" effect. In the last major ice age the giant lizards ( dinosaurs) couldn't handle it but the little furry mammals (our ancestors) just about made it through by becoming subterranean and by not being picky about what they ate.
Having said all that, if I was in charge of the security services I wouldn't probably recommend that such information from the scientific community, about a coming asteroid, should be leaked to the public because of the moral chaos it would cause. Yeah, then i'd start diggin'.
Well actually I'm being facetious a massive subterranean bunker building campaign would have to take place.
2.19 They shall rejoice, our chosen: who sorroweth is not of us.
2.21 We have nothing with the outcast and the unfit: let them die in their misery. For they feel not. Compassion is the vice of kings: stamp down the wretched & the weak: this is the law of the strong: this is our law and the joy of the world.