Who would win?

[A.Saturnus]

But Godzilla was born in a thermonuclear explosion. And fusion reactors don't exist. Wow, I am such a nerd using that arguement in this thread.

There are fusion reactors. The experimental reactor ASDEX-upgrate in Garching, Bavaria is in fact a functional fusion reactor.

It´s clear that superman would win. The only thing that can wound him is cryptonite. It´s unlikely that godzilla could come up with that.