The familiar headlong rush with which the culprits of a terrorist attack are pronounced with certainty barely minutes after it happens has rarely been more decisively skewered than on Wednesday morning.

France woke up to the news that it was not, as the media had spent two days insisting, a crazed fascist who had murdered three North Africans and four Jews in two separate attacks. It was a suspected al-Qaeda terrorist.

So the parallel was not with Oklahoma City, where the white supremacist Timothy McVeigh killed 76 people in 1995. Rather, the Toulouse murders were France's 7/7. The numbers who died may not compare, but as an act of home-grown Islamist terror, the murders are just as shocking.

The most significant category error was made by those who immediately asserted that, because the murderer had killed North Africans and Jews and so had to be an all-purpose racist who hated Muslims as much as Jews, he had to have been a product of the anti-immigrant climate in France.

But that is to ignore one of the most fundamental points about radical Islamist ideology. As Ed Husain points out overleaf, al-Qaeda has murdered more Muslims than non-Muslims.

Others have written about the long history of French antisemitism. That is of course a cancer which still remains, and which requires constant vigilance. But in the context of these murders, it is entirely irrelevant. The terrorism behind such attacks is a very different phenomenon which, even after 9/11, the Madrid bombings, 7/7 and the many other radical Islamist attacks, is still dismissed by some as simply a contemporary equivalent of groups such as the Baader-Meinhof gang, the Red Brigades and the IRA.

The threat posed by radical Islam is far deeper than this. It endangers the very fabric of Western civilisation.

And yet, astoundingly, there are those in our community, and elsewhere, who continue to treat with its allies.