The guided-missile cruiser USS Philippine Sea launches a Tomahawk cruise missile, as seen from the aircraft carrier USS George H.W. Bush
Overnight:
The United States and five Arab allies launched a wide-ranging air campaign against the Islamic State and at least one other extremist group in Syria for the first time early Tuesday, targeting the groups’ bases, training camps and checkpoints in at least four provinces, according to the United States military and Syrian activists. [...]
The intensity and scale of the strikes were greater than those launched by the United States in Iraq, where it has been bombing select Islamic State targets for months. The air campaign also marks the biggest direct military intervention in Syria since the crisis began more than three years ago.
President Obama is scheduled to deliver a statement on the situation at 10 AM ET. We will be liveblogging his remarks.