Is God All Powerful?

I'm working here with the classical conception of God, according to which God is all powerful or omnipotent. Now certainly, he could make a deterministic world in which everybody did what he determined to do but that wouldn't be a morally significant world. It seems to me that classical theism, which affirms God's omnipotence and all goodness, is logically compatible with evil. So I think it's best to start with the strongest conception of God and work from there.