Originally Posted by
Alan2099
Cyclops had been acting less and less rational and more and more aggressive in the events leading up to AvsX. By the time the story started, he'd already formed a wetworks team using mentally unstable teenagers, declare himself the final authority on all things mutant, formed his own country in US waters and threatened the governments of the world.
By the time A vs X rolled around, he was basically going, "I know Phoenix has never re-powered mutants on a planetary scale before or anything even remotely like this, but I'm pretty sure that's what it's going to do this time. I just have a hunch. It's totally going to do that and not destroy the planet, which is what is IS doing right now and has a history of."
It's no wonder at that point that the Avengers really didn't want to listen to him.
Maybe it was the stress, maybe hanging around Magneto and White Queen had started rubbing off on him, or maybe he was finally going through the awkward teenage rebellion phase he skipped growing up, but the guy wasn't exactly being the most rational of superheroes.
Then he and his guys took over the world and he killed Xavier, but that's totally not his fault. it's the fault of Phoenix... the thing that the Avengers didn't even want on the planet and Cyclops was welcoming with open arms.