One real problem is our response time with visa's that expire. I've always thought that no country should have more visitors than we can track. I think visitors should be bugged before the visa's expire after this incident.
The terrorists were here on education visa's that had expired.
Also a common sense approach to monitoring Muslims given their history is warranted. The FBI positioned themselves in Catholic and Baptist churches in order to monitor them. They cracked down on a Jewish temple that was making an escape tunnel in case of a violent attack as well.
WHEN Christians, Jews, Buddhists, Toaist, Hinduists, and Pagans start bombing buildings in the name of their religion then they should start putting already scarce resources in heavily investigating those religions.