Blocking Muslims entirely from entering the country may only further radicalize the Muslims that currently live within the country. That won't stop the problem of terrorism it'll exasperate it.
Once it becomes okay to block a specific group of people, it becomes easier to block the next group you don't like, and then start kicking people out because they're different than you. None of it will end up well.
You mean by leaving Iraq the fukk alone in 2003? Yeah Mr. Hindsight that could've help a lot.
The issues of the Middle East and even Al Qaeda/ISIS specifically go back much, much farther than 2003 and Iraq. The US specifically has been intervening in ME affairs since WWII, including overthrowing the democratically elected governments of Syria and Iraq in the 40s/50s. Of course, the formation and support of Israel has always been an issue as well. Spreading out to include "The West" and not just the US, this conflict has been going on for centuries.


all around. Sorry for the loss of life though.