After spending nearly six years of his presidency installing a series of constraints on U.S. counterterrorism operations, President Obama has launched a broad military offensive against Islamist groups in Syria that stretches the limits of those legal and policy enclosures. The barrage of airstrikes was aimed mainly at a militant group, the Islamic State, that is no longer among the al-Qaeda “associates” envisioned by the military authorization passed after the Sept. 11, 2001, attacks. The group is not even suspected of planning attacks against the United States.

The unfolding U.S. air campaign has employed weapons — including dozens of 3,000-pound Tomahawk missiles launched from U.S. warships — that have flattened targets in ways destined to test Obama’s doctrine requiring “near certainty” that no civilians be killed. [Link]