The war "could provide some form of twisted inspiration," he warned.
It's gone from "substantial" to "severe".
"Of course there are likely to be terrorist attacks on UK soil on my watch. We wish it were not so," said Ken McCallum
MI5 Chief Praises England Football Team As He Warns 'Toxic Racism' Online Fuelling Far-Right Terrorism
Ken McCallum says UK should "own" the problem rather than blame foreign troll farms
Ken McCallum to deliver annual threat update
New Security Service director general Ken McCallum reveals it has been "outright racist" in some cases in the past.
Exclusive: Ex-shadow chancellor says there should be a free vote on laws that will allow undercover MI5 and police informants to commit crimes.
The Intelligence and Security Committee (ISC) took evidence in secret from MI5.
Foreign affairs committee chair Tom Tugendhat tells HuffPost UK's Commons People podcast there are "serious questions" for spy agencies.
There are a grand total of 175 redactions in the report. Here are the key passages that have left us scratching our heads.