Here is the problem:

Marine Le Pen, head of the anti-immigrant National Front, disparaged the government’s efforts against terrorism.

“The war against the scourge of fundamentalism hasn’t started, it must now be declared,” she said in a statement. “That is the deep wish of the French, and I will put all my energy so that they are finally heard and the necessary fight is finally undertaken.”

A French parliamentary report released July 5 said France’s failure to prevent last year’s attack was partly due to lack of coordination between the country’s six intelligence units, and recommended the creation of a single counter-terrorism agency.

But look:

Police killed the driver of the truck, a 31-year-old Tunisian with French residency. While the government and French judicial system are treating the attack as Islamic terrorism, media reports have cited neighbors of the suspect as saying he was going through a divorce and wasn’t religious.

The BBC reports that the man, Mohamed Lahouaiej-Bouhlel, was not on the radar of French authorities as a terrorist sympathizer. In fact, we was a wife-beater whose wife had had enough of him:

Outside the flat in the Route de Turin where he had been living, residents of the four-storey building described the man as a loner who never responded when they said hello. He would often be seen climbing the stairs to his first-floor flat, carrying his bike, they said.

Although the attacker had a pistol, all the other weapons found in the lorry turned out to be fake, which raises questions about the extent of support he had from jihadist groups.

The story may change as police sift through the evidence they gathered in their raid of Mohamed Lahouaiej-Bouhlel’s home, but this sounds a lot like what the Orlando shooter appears to be: a violent head case who wasn’t especially religious, but who used radical Islam as a rationale for releasing the murderous impulse held inside.

I don’t intend this to downplay the political and religious meaning of these acts; there are countless French and American men who are violent, and whose lives are falling apart, but they don’t commit mass murder in the name of jihad. What I’m saying is that even if you agree that Something Must Be Done, what, exactly, can be done to anticipate and neutralize men like Mohamed Lahouaiej-Bouhlel.

You could stop all immigration from Muslim countries, and expel all non-citizen Muslims, I suppose. Even then, you would have millions of French citizens who are Muslims. How do you prevent them from snapping like this guy apparently did? If they have no public record of Islamist sympathy, how do you read their minds? Besides, what kind of world would this create for the vast majority of French Muslims who have done and will do nothing wrong, and may even despise the jihadists as much as non-Muslims do? How can that be just?

It is true that ideal justice must take a back seat to a society that’s fighting for its life under attack. And it’s true that every attack like this pushes the French closer to the edge of concluding that they are in just such a fight. If a French family cannot go out to watch the fireworks on Bastille Day without having to worry about a Muslim running them down with a lorry, then the French will not be willing to live in that kind of state indefinitely. Nor should they.

Something Must Be Done. Really, something must. But what effective thing can be done?

There is this: Europe must close its borders to the flood from the Middle East. It only invites this kind of thing to occur infinitely over the decades to come. If Angela Merkel and the other Eurocrats won’t do that, the European publics will elect leaders who will. Mohamed Lahouaiej-Bouhlel was not one of the refugees, but aside from bringing in actual terrorists masquerading as refugees, Europe is important young Arab Muslim men who are unlikely to find employment, and who are highly likely to find nothing but frustration in the West. This could easily be fatal for untold numbers of Europeans.

UPDATE: This, from reader Devinicus, puts it pithily:

If there is nothing a free society can do to stop Islamic terrorism, that society will not long remain free.

That’s where France is headed, I’m afraid, not because the French want it, but because terror will make them desire it.

UPDATE.2: A European reader e-mails:

It happened again. A large attack on European soil, with close to 100 persons dead (at present count). And all I can feel (and notice from other people) is emptiness. It’s like the will to talk about resistance and fighting is suddenly broken. Sure, in some ways, the debate is in better shape now, compared to before Paris.

There is an ongoing debate about the inherent problems with radical Islam, and about the dire need to integrate/assimilate the large numbers off middle eastern/African refuges into the European states.

But when it comes to this sort of attacks, there is no longer anything to say. It’s an enemy that can hardly be fought, and that can hide practically anywhere. After Paris, we talked about striking back, and bringing the fight to them, but now, it’s just empty glances and silence. And with the growing lack off Christianity in large parts of Europe, I fear that some of our spirit in “finally” broken. I seek shelter in these words “Do not be afraid of those who kill the body but cannot kill the soul. Rather, be afraid of the One who can destroy both soul and body in hell.”