Here we go.

The NYT reports that French prime minister Manuel Valls is edging into the kind of war-on-terror rhetoric that has gotten America into such trouble—wars, Patriot Acts, surveillance state—in the aftermath of 9/11. "It is a war against terrorism," he declared, "against jihadism, against radical Islam, against everything that is aimed at breaking fraternity, freedom, solidarity."

And does this sound familiar?

Top ministers in the French government were scheduled to hold an emergency session on Saturday to discuss measures to prevent a repeat of the attacks, which shocked the country and raised questions about why law enforcement agencies had failed to thwart terrorism suspects well known to the police and intelligence services.

Valls is a Socialist with Swiss/Catalan* roots and, according to Wikipedia anyway, has said some dubious things about race and immigration—including, apparently, getting caught on camera saying that showing more white people would give a better picture of Évry, where he was then the mayor. Valls also decided to expel a 15-year-old Roma girl—Leonarda Dibrani—and her family to Kosovo after she was arrested for being undocumented during a school field trip.

That decision was met with a 74 percent approval rating—57 percent approval from the left, 89 percent from the right—while President Hollande's more equivocal response is seen to have cost him support.

Clearly, Valls (who is said to be ambitious) represents some deep-felt anxiety and frustration about immigrants in France—and it looks like he's milking it, Rand Paul-style, in a moment of deep national vulnerability.

As we've seen, declaring a war on a phenomenon—war on drugs, war on terror, J. Edgar Hoover's "war on crime"—doesn't always end well. (Valls also opposes legalizing marijuana.)

“There needs to be a firm message about the values of the republic and of secularism,” Mr. Valls said in his speech in Évry, then talked about a massive solidarity rally scheduled for tomorrow, which is supposed to bring heads of state from Germany and Turkey, as well as prominent Muslim leaders. “Tomorrow, France and the French can be proud. Everyone must come tomorrow.”

What happened this week in Paris was a catastrophe, and politicians have a duty to respond to catastrophe—to show leadership, and plot a course for their confused and angry constituency. But they also have a duty to be cautious.

As those of us who lived through 9/11 in the US know all too well, this is an extremely delicate and dangerous moment. The country is emotional and vulnerable—and might be willing to agree to things it will come to regret.

* His Catalan connection might be indicative—that region of Europe, like the Netherlands, has long considered itself urbane and super-liberal (it was/is an anarcho-communist hotbed that suffered and resisted mightily under Franco's fascism) but has spent the past 15 years having a serious identity crisis over its internal xenophobia and its inability/unwillingness to deal with the immigration question and the inevitable diversity of a global economy.