If Islamic extremists really love their religious institutions in the way that they claim they do, then pointing an ICBM at Mecca may not be the most irrational thing to do. They may not care if the rest of the world goes up in a nuclear mushroom cloud, as Bill points out, but Mecca is not the rest of the world. Would they really risk blowing up New York City if they believed the consequences of such an action would be a 30 kiloton nuclear explosion over the Kaaba stone? After all, the nuclear destruction of Mecca would end Islamic forms of worship as they presently exist.