The good news is that the international coalition, in which our military contributes, has done a lot to reduce the ground space, the territory in Iraq, Syria that ISIL once occupied a couple years ago. That's a good thing. And a lot of that, frankly, has occurred in Trump administration, so I'll give them credit for that.

I think that the potential for homegrown terrorist attacks is something that we have to be very concerned about, because, in many respects, it's harder to detect when you have an independent actor who may be living in our midst, in our own communities.

The good news is that the international coalition, in which our military contributes, has done a lot to reduce the ground space, the territory in Iraq, Syria that ISIL once occupied a couple years ago. That's a good thing. And a lot of that, frankly, has occurred in Trump administration, so I'll give them credit for that.

I hope that the states are taking seriously their obligations to harden the cybersecurity around the election infrastructure that Americans rely upon and need.

With every case from years ago there should be lessons learned.

President Trump talks about extreme vetting, and we actually do have extreme vetting when it comes to refugee resettlement. Refugee resettlement is the most thorough, cumbersome, multilayered vetting system we have for the admission of anyone to the country.

If you build - if you spend billions of taxpayer dollars to build a wall over, let's say, a mountain, if you build a 10-foot wall over a 10,000-foot mountain, and someone is determined to climb the 10,000-foot mountain, they're not going to be deterred by the 10-foot wall. It's a matter of common sense.