I think that ISIS is a problem and it's really a symptom of a much greater problem.

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.

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

In my view, and in the view of a lot of intelligence experts, the terrorist threat that we face now has morphed significantly from the days of 9/11 to homegrown violent extremism. We have to be concerned and focused on homegrown violent extremism, countering violent extremism that exists within our borders.

The Secret Service hates to complain about something. They're secret by nature. They're not boastful; they don't like to be in the limelight. And therefore, they need middle management, i.e., a Cabinet-level person, to be their advocate, to Congress, to the White House, to ensure that they have adequate funding.

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.

I'll never forget what a Catholic priest told me; he said, "If you try to padlock the door, you have to give people an alternative path - an alternative, safer path. You can't padlock, and you shouldn't padlock a burning building."