The strategy remains the same.

These are not isolated, lone wolf, spur-of-the-moment attacks.

Although not necessarily difficult to execute, these attacks still took planning, preparation, training, sourcing of weapons and explosives, reconnaissance of the target and the careful recruitment of so-called “martyrs” – fanatical young men prepared to carry them out in the full knowledge they will probably die doing so.

This is far more reminiscent of al-Qaeda’s modus operandi in the early 2000s, going for big publicity, high-casualty attacks that make headlines around the world.

Western counter-terrorism officials had recently come round to the conclusion that while there were still people aspiring to such grand-scale attacks, the prevailing threat was more likely to come from “self-starters”, people like the murderers of British soldier Lee Rigby in Woolwich near London in 2013.

In the light of what has happened in Paris and elsewhere, they may now be revising that assessment.