First there was the attack with a car on two police officers on Montreal, then two days later came the assault on the honor guard of Canada's National War Memorial and shooting in the halls of Parliament in Ottawa. The victims - randomly selected. Just like the ones at the attack in the Jewish Museum in Brussels last May, or the two British soldiers one year before, who were stabbed in broad daylight on a London street by two assailants.

The prevailing culprits: fanatical Muslims. These indiscriminate acts of violence in the middle of bustling Western metropolises are causing a lot of anxiety. It should cause anxiety. That's the point of terrorism.

This can happen in Germany, too. Even today. Or tomorrow. Fanatical Muslims live here, as well. More than 450 of them are thought to have already left for Syria or Iraq, presumably to join the ranks of the "Islamic State" (IS) terrorist group. Around 100 of these people are already back in Germany, more radicalized than they were when they left. Now they have fighting experience. They are used to brutality. Potential ticking time bombs, security experts say.

Absolute security?

How to handle this danger? Can we really protect ourselves from it? We, who give so much importance to security and are always sure to wear a helmet when we ride our bicycles or go skiing. Because we want to protect ourselves.

But if we are being honest with ourselves, we must admit: There is no absolute safety. Not in the face of aggressors like the ones in Montreal, Ottawa, Brussels or London.

Is that tragic? Not at all. We forego total security in many aspects of our lives. Many more people in Germany are involved in fatal car accidents while on vacation or die while cleaning their windows than in acts of terrorism. And yet no one is going to give up their chance to travel or stop opening the blinds.

Stephen Harper

My hero this week is Stephen Harper. The Canadian prime minister, after two attacks in his country in one week, gave a self-confident message - and really the only possible one - to his people: "We will not be intimidated!"

We will not be intimidated. The means nothing other than: We want to remain an open society. We want to remain a free society. And we want to remain a lawful society.

That is why everyone in the free societies of the West must continue to live unperturbed and free from suspicion - be they Christian, Jewish, Muslim, Buddhist, or atheist. And that is why these societies remain open to immigration. All the more important, in fact, when immigrants have risked life and limb to escape their homelands. No society that wants to remain an open one can say, "We will only take in Christians."

We are a free country, and we will continue to exercise our liberty. We will put on Christmas markets and visit them by the thousands. We will continue to go to soccer stadiums, and men will even watch women play - even though the women are wearing shorts!

We will simply continue living as we always have, and will try to think as little as possible about where danger might be lurking.

Tolerance and the rule of law

A free society is, above all else, else a tolerant society. Here, everyone is allowed to think and say what they like. Tolerance begins to disappear when the actions of a few begin to impinge upon the liberty of others. And especially when it comes to the basic principles of living together. It is a specifically German lesson, culled from this nation's history, that the state does not have to grant its enemies a free hand. Therefore, the prohibition of jihadist propaganda in Germany is perfectly fine - and is not contrary to these principles.

The strength of a society proves itself in a crisis when people remain committed to their principles, even when it comes to their enemies. And when they don't, under the pretense of a suspicious phone call, freely eavesdrop, arrest, revoke passports or nullify citizenships. Or create a space without rights, like the Guantanamo Bay prison.

Rule of law is a value in and of itself. All are equal before the law. Even when radicals try to rob us of our dignity and attack citizens of our nations in front of live cameras like animals, we will not be intimidated. Anything else would be a victory for terrorism.