Nothing can defeat Godzilla. He is the embodiment of the Earth's anger and sorrow. His plot armor is the thickest of all. Your only hope is to make him lose interest in you.
You may destroy the body, but not at the loss of countless soldiers. Everything involved in this battle would be covered in indestructible G-cells. Once anybody returned to space, you would then have a legion of Space Godzilla to contend with in a few years.
Until the scars of the Earth heal, there will always be Godzilla to remind us of our most grievous sin.