Perhaps, but stuff like this is far more likely to kill America than letting in someone who made a post. Just like I believe the Patriot Act was more destructive than 9/11. I'm more interested in actual criminal or destructive action that people have taken.
Discussion
And honestly, I feel like my government is far more of a threat to me today than any foreigner. That's the problem with letting seemingly small things like this go for too long. It's always a matter of time before the tool is turned inward. We've seen that before.