It’s possible that the only lesson we can learn from Paris is regret.

Regret for the countless beloved dead. Regret that our sentiment didn’t reach to Beirut, to Damascus and beyond. Regret at the backlash we know is coming.

One of the first measures French President François Hollande was the closing of the borders. Ostensibly, this was to prevent more attackers from joining in the wave of terror still roiling Paris at the time of the announcement, and to prevent the perpetrators from fleeing.

But implicit to this measure is the assumption that foreigners did this; that no true Frenchman could do such a thing.

The ideological fight is being imported into France, that’s true. It is the extension of the ongoing war waged by extreme Islamists who oppose what they call the imperialism of the morally decadent West.

This is classic al Qaeda methodology: hit the soft targets, terrorise the civilian population and drive western governments to further abridge the freedom of their own people in order to destabilise and disrupt government, society and culture alike.

Drive foreign governments to strike harder against the Muslim peoples, creating more resentment and hate, and more soldiers for radical Islam.

This particular series of attacks was aimed at Paris’ youth. The terrorists didn’t attack the Champs Elysées, the Eiffel tower, Notre Dame or the Louvre, where the most tourists gather. They didn’t hit the Left Bank, where many government offices are located.

They hit central Paris. They hit clubs, bars, restaurants and a football match. They stole the lightness from the hearts of a generation of French youth, who will never go out again without wondering if, not when, they’ll be coming back.

Al Qaeda, ISIS, Wahabism—intolerance in all its forms—is a self-perpetuating phenomenon. It feeds on fear; it breeds fear. It needs fear. Its seed lives in every heart. In those of Frenchmen, too.

But what can we usefully do? What can anyone do, once we’ve pasted the tricolor over our profile pic, and somewhat guiltily added, “and Beirut, too!”

Not much. A lot. We can welcome strangers and strange ideas. We can refuse to fall victim to the enemy’s tactics; we can refuse to hate all Muslims (or foreigners, or religionists of any stripe, or women, or…). We can denounce intolerance in our own lives.