A small correction in your post. The problem is not radical Islam but the fact that Islam as prescribed from the Koran is radical. In fact moderate Muslims are apostates and as ISIS has shown us in horrid executions of men, women, and children, moderate Muslims are slaughtered, raped, butchered and worse.
The Koran if followed as written is radical and without mercy. A moderate Muslim is an apostate and in the eyes of ISIS even worse than Christians and Jews.
ISIS is an evil entity that will win or it will die. If they win we die. If we win they die.
If they don't die we haven't won.
They must be destroyed to the last man. And woman.