The Eiffel Tower was engulfed in darkness on Friday night. Today, schools and government offices in France are closed down until further notice. The borders are closed, a curfew has been established, and the country is considered to be in a state of emergency.

Still, thousands of citizens gathered in the streets this weekend to proclaim one message: “Not afraid.” Even after watching on video people running for their lives from a crowded theater, after witnessing the carnage left in the wake of Friday’s attacks, the people of France made it clear that the most powerful weapon in the terrorist arsenal — fear — would not win.

The march of the Islamic State in the Middle East takes a new turn with the recent events in Europe. The War on Terror has entered a new phase, where the violence we have sought to contain in Middle Eastern countries is sweeping into other societies — bringing violence, causing heartbreak.

When I think of the ways the Islamic State could achieve its objectives in its war against the West, I consider its militant plans and our government responses. Yes, there are well-worn paths of appeasement or containment, which are reminiscent of Europe’s bumbling into World War II. There is always the specter of nuclear warfare or the random targeting of unsuspecting civilians.

I cannot speak to the possibility of the Islamic State scoring military victories against the United States or Europe, because we cannot look into the future to see what kind of forces will be marshaled against us. But I do know this – one way that the terrorist wins is by immersing the world in fear.

Terrorism thrives on fear, and fear — if left unchecked — can spread into the deepest, darkest corners of our hearts and lead to decisions and choices that, in normal times, would be unthinkable. The apostle John wrote in the New Testament of “perfect love driving out fear.” From a Christian perspective, there is no fear in love because love is the primary purpose for human existence. There is no fear of God’s judgment when we love as we ought.

Almost a thousand years ago, the Christian theologian Thomas Aquinas, whose interactions with Muslim thinkers led to some of his greatest works, wrote, “Fear is such a powerful emotion for humans that when we allow it to take us over, it drives compassion right out of our hearts.”

Aquinas is right. Fear and compassion cannot coexist. The former inevitably drives out the latter.

So, in the midst of a worldwide battle against the evil of Islamic terrorism, we must make sure that we do not allow fear to overwhelm our hearts, crowd out our compassion, or fundamentally change our character. For compassion to win, courage must conquer the fear in our hearts.

Already, we have seen a growing backlash regarding the refugees displaced in the war in Syria. There is widespread fear that terrorists are streaming into Europe or America alongside frightened refugees.

What is the courageous response? To close the borders for good? To turn away thousands of families and children who, through no fault of their own, have been victimized by war and violence and long for peace?

It is fear that drives out compassion toward our fellow humans suffering under the weight of injustice and violence. Fear, not courage.

Courage calls for prudent compassion. It is not anti-refugee or anti-Muslim to enforce the strictest standards of security, to ensure that countries remain safe and citizens secure. Such is the way of wisdom. But fear walls off our hearts to our fellow human beings in need of help. Courage opens the door of compassion, and with wisdom and prudence, ensures that we live up to our highest ideals while also securing the peace of our civilization.

Courage also calls us to stiffen our spine against the criminals who would conquer us. As we denounce these acts of violence with every fiber of our being, we cannot ignore the fundamental religious nature of this clash of worldviews. Whether or not we believe the Islamic State to be the inheritor of “true Islam” or a cruel distortion that is ravaging the world, there is no question that theology lies at the heart of today’s terrorist activity.

Fear leads to hatred; courage leads to convictional compassion. And convictional compassion means differentiating between the radical Islamists who would destroy us and peaceful Muslim neighbors who stand with us in deploring such violence.

We are in a war. An unconventional war, of course, but a war nonetheless. Wars always bring out the best and worst in humanity. When future generations look back in time, let us hope they will see that we met these challenges with courage, not fear. In doing so, we obey the most frequent command in the Bible, “Do not be afraid.”

Trevin Wax is managing editor of The Gospel Project and author of multiple books, including “Clear Winter Nights: A Journey Into Truth, Doubt and What Comes After.”

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