It took nearly 21 years, but the U.S. finally removed al Qaeda leader Ayman al-Zawahiri from the terrorist battlefield. President Biden said Monday evening that Osama bin Laden’s longtime deputy was killed Sunday in a counterterrorism operation in Afghanistan that others confirmed as a drone strike.

As Mr. Biden noted, the strike brings another measure of justice for the victims of the 9/11 attacks that killed nearly 3,000 Americans on U.S. soil. The 71-year-old Egyptian co-founded al Qaeda and helped bin Laden build an operation that could spread radical Islam and murder innocents without remorse.