Indeed he/she/they did allow free will, because without free will there would be no true love. BUT, an all knowing and all powerful God could see the eventual outcome of allowing freewill being nuclear armageddon (as you've pointed out) in which case, he/she/they directly chose not to intervene despite mountains of suffering they were fully aware was going to happen. If God is already aware of who can and will repent and who won't, then it follows we can skip the painful interesting part and be sorted directly into heaven and hell.... if God is unsure and wants us to choose by virtue of our actions, then he/she/they is not omniscient. Unless of course, God be Quantum. ;o)