We have this unfortunate habit in the United States of dividing terrorism into different categories. External, foreign terrorism, which manifests itself overseas or in the United States, or domestic terrorism.

ISIS rules Muslim apostates every day and then beheads them. Poorly educated guys get Islam for Dummies, petty criminals who think they're suddenly changing their lives because they see the light. The best way to fight them is to show them they don't know Islam at all, and that they are in fact working for the other side.

The ghost caliphate will be a virtual organization it'll be decentralised, with no leadership, and it will just encourage people to keep acting now that the caliphate's gone, that individuals should go do self-starting jihad. Get a gun, get an improvised weapon, take your car, and carry out the jihad.

When we use the word domestic [terrorism], we discount its actual impact as political terrorism, which is, of course, political violence meant to impact an audience outside of the immediate victims.

Now you have Donald Trump ready to execute policy on the basis that the Muslims are the problem, not ISIS. Oh Jesus, it's a circular firing squad.

Law enforcement does counter political extremism here in the United States in the exact same way that they do political extremists who are infiltrated into the United States, who may come from a religious motivation, as we saw overseas in Europe. But the same methodologies have to be used.

Trump doesn't understand the counterintelligence process. Take, for example, Carter Page. He's been appearing on television and acting as though the U.S. intelligence community monitoring his activities in Russia and suspicions that he may have been in league with Russian intelligence is an affront.

There's only two classes of people: terrorists and non-terrorists. Terrorists come in every flavour: there are Buddhist terrorists right now killing Rohingya in Burma! Buddhists! They're not allowed to kill bugs.

You can`t differentiate between an Islamic terrorist and a Christian terrorist. Or a politically motivated terrorist who`s anti-abortion or someone who may have differing views.

Arson is the single most fundamental form of terrorism.It`s the simplest terrorist tactic.