Last week's terror attacks on Brussels are a horrific reminder of the grim reality of the fight against the Islamic State extremist group. The bombings at the airport and metro, which killed at least 31 people, including three suicide bombers, and wounded more than 300 others, were a savage attack on innocent civilians, an attempt to shift attention as Islamic State forces lose ground on the battlefield. The atrocities must also remind us of Islamic State's goal to bring us down to its level: The group wants the West to abandon the values that give us both the moral high ground and the means to defeat it. It wants us to declare a civilizational war that will confirm the Islamic State message that Muslims cannot coexist with the West.

It is believed that five suicide bombers attacked the Brussels airport and subway on March 22. Three of the men have been identified; the fate of the other two is unknown. One is thought to be on the run and the other may have been killed in the attacks. The Islamic State group took credit for the bombings in Brussels, just as it claimed to have been behind the coordinated series of attacks in Paris in November that killed 130 people.

Investigators believe the same terror network was responsible for both assaults. On March 15 and 18, Belgian authorities raided two suspected hideouts; at the first they had a shootout that left one person dead and found Islamic State literature, weapons and explosives. Two other individuals escaped and they are thought to have been involved in the suicide bombings a week later. Evidence seized there led them to a second location where they found Salah Abdeslam, along with several others, who is suspected of being involved in the Paris attacks.