If I could push a button labelled, "kill everyone on earth," I would think really hard over whether or not to do so...

I wouldn't think. I wouldn't push the button, period. Then I'd take it apart and get thebutton switch and uses it for something other than a doomsday machine.

Oh, I don't think it would be hard.

Just keep in mind "kill everyone" means you too.

Killing everyone on earth would leave the vast majority of life unharmed, and with a much better outlook.

Can you imagine the explosion in the carrion-eating population? With so much food around, generation gaps in the termite population will shrink so far that within decades they'll evolve (distinction unclear and unecessary) to the point that they'll be eating our concrete & steel structures for further decades to come.

MC- I'm not afraid of dying.