Quartz

The U.S. began airstrikes in Syria on Monday, fulfilling President Barack Obama’s vow to “degrade and destroy” the extremist group that calls itself the Islamic State. The Pentagon said it deployed bombers, fighters, and cruise missiles against ISIS forces within Syria, and a U.S. defense official told ABC News that “several Arab nations” are also involved in the operation.

The military operations within Syria bring the total number of countries targeted by U.S. airstrikes since September 11, 2001—either by conventional planes and missiles, or by armed drones—to seven. In addition to Syria they include: the long-running U.S. military campaigns in Iraq (which has now been bombed by four consecutive U.S. presidential administrations, dating back to 1991) and Afghanistan; drone attacks on Islamist militant groups in Somalia, Yemen, and Pakistan; and NATO-led operations against ousted Libyan dictator Muammar al-Qaddafi.

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