Can Godzilla really be considered an invader, given they frequently simply stomp-and-leave, or defend against others - who would stomp-and-leave (or occasionally set up shop) - by stomping-and-leaving? When I think invaders, I think intent-to-occupy; Godzilla seems to have no interest in occupying any Tokyo estates. Where there's no intent to occupy, I consider them to be just destroyers.
Hmm. Would obliterating something (and leaving) count as an invasion? To take it to ridiculous proportions: say we blew up another planet. Did we invade it?
To be fair, at the time of writing, it was pretty difficult to destroy another nation's cities/property/wealth without physically entering and being next to them.
Invading, no. They are not a governing body.