Was John evil?
I know that he was the commander of the fleet that slowly invaded Earth and so responsible for all the Visitors who murdered innocent people under his command.But it did seem at the end that even he had his limits as he was unwilling to use the Doomsday weapon to destroy Earth and admited defeat unlike the genocidal Diana who was more than willing to blow up Earth out of spite.I wish there had been more focus on John to see if he fully beleaved in what the Visitors planed for Earth and humanity.
So it's treason then!