It has been reported that both suspects were legal permanent residents, that one was a naturalized citizen and the other was on the path to becoming a citizen. What deficiencies are there in our immigration and visa system that would have allowed this? We have already seen radicalized citizens, but is there a way to detect extremist behavior in those still on the path to citizenship? What kind of safeguards can we implement that might prevent granting them citizenship?

In 2002, Congress created the National Security Registration System, but it was suspended in 2011 by Department of Homeland Security Secretary Janet A. Napolitano. We know that system had problems, but the basic premise behind it — that extra screening is necessary for immigrants from nations that have a higher population of extremists — needs to be revisited and reinstituted. This should be a part of any comprehensive immigration reform.

In my home state of Kentucky, our refugee program has proven to be a problem. On Jan. 29, two Iraqi citizens living in Bowling Green, Ky., were sentenced to long prison terms for participating in terrorism and providing material support to terrorists while living in the United States. Does the current immigration reform address how this might have happened? Regardless, we need more scrutiny when accepting refugees from high-risk nations.