Why Did God First Send Satan To Earth Knowing That He Would Create Havoc With Adam And Eve?

Satan had corrupted the earth before God created Adam and Eve. The earth was Satan's place, so why would God create them on earth and not in a Holy place without Satan? This would be like if I let my children swim in a lake full of crocodiles and not watch over them! I know that by these questions, I am getting on some Christian's nerves, but no one in the future is going to believe that God is just because of this.