MI5 Chief Warns Next 9/11 Shock Already Forming

The head of Britain's domestic intelligence service says the next mass-casualty shock may already be in preparation somewhere Western spy agencies are not watching.

MI5 Director General Sir Ken McCallum warns that a new strategic shock on the scale of 9/11 could already be taking shape undetected, in an opinion piece published Friday to mark 25 years since the attacks.

"The uncomfortable truth is that the next strategic shock may already be taking shape somewhere we are not yet looking," McCallum wrote in the commentary for The Independent, according to Reuters.

He says the agency he leads in 2026 faces a threat landscape "markedly different" from 2001's — terrorism plus what he calls "strategic national security threats posed by capable States."

The Warning

McCallum's central argument is against fighting the last war. "We must of course always learn from the last attack – but must beware of preparing brilliantly to fight yesterday's enemy, using yesterday's methods, against yesterday's target," he wrote.

Citing former CIA director James Woolsey's line about the West slaying "a large dragon" after the Cold War, McCallum adds: "We now face the worst of both worlds: dragons are back, but snakes persist." The Independent identifies the dragons principally as Russia and China, and the snakes as radical Islamic extremists.

He points to state-backed aggression "whether sabotage subcontracted to criminals, or covert interference in our democracy, or destructive cyber attacks on power stations," and says it "demands new laws as well as new tradecraft."

Al-Qaeda, he says, remains a threat, but its capabilities are "a fraction of 2001's." He cites a recently foiled Islamist plot to kill hundreds in gun attacks on the Jewish community in Manchester as evidence that mass-casualty ambition endures.