A solidly made argument. The cost of not crushing the Islamic State is also a diaspora of Muslim terrorists though, just more of them for a longer period of time. But the real enemy is the Muslim Brotherhood.
"The first thing you have to do is admit it is an ideology"
That shouldn't need to be said. But since it does, Islam is the threat doctrine behind a substantial majority of the world's problems today, aided and abetted by the contemporary forms of Marxism we see having escaped the Frankfurt School.