That bomb that took down that Russian airliner may have been the size of a soda can. And that bomb killed more people than all the Paris attackers combined. So this is still a grave threat.

I'm just concerned that as long as this caliphate exists, it provides this magnet for radicalization, and we're likely to see more attacks like we have seen in San Bernardino, Chattanooga and elsewhere, and that's the concern I have over pace.

The intelligence community is very professional, they do their jobs well, they're the best intelligence gatherers in the world. They're dedicated, patriotic Americans. They will work with any president. They want to have a good relationship with every president.

The president [Barack Obama] is not willing to send in apaches and spotters if the Iraqis say they don't want them and if it means that these Shia mobilization forces are going to be going after and trying to kill Americans.

I would need to see changes in the Iraq governance. Otherwise I don't think strikes are going to have any impact and could be very well counterproductive.

There are perfectly appropriate circumstances to unmask the names of people. In fact, that is done quite often. And the standard is whether the unmasking of those names is necessary to determine the significance of the intelligence.

The war in Iraq has been extremely divisive here at home, and has also divided the world community.