CENTCOM released this statement yesterday:

TAMPA, Fla., Aug. 18, 2014 — U.S. military forces continued to attack ISIL terrorists in Iraq Monday, using a mix of fighter, bomber, and remotely piloted aircraft to successfully conduct 15 airstrikes near the Mosul Dam.

The strikes damaged or destroyed nine ISIL fighting positions; an ISIL checkpoint; six ISIL armed vehicles; an ISIL light armored vehicle; an ISIL vehicle-mounted anti-aircraft artillery gun, and an IED emplacement belt. All aircraft exited the strike areas safely.

Since Aug. 8, U.S. Central Command has conducted a total of 68 airstrikes in Iraq.  Of those 68 strikes, 35 have been in support of Iraqi forces near the Mosul Dam.  These strikes were conducted under authority to support Iraqi security forces and Kurdish defense forces as they work together to combat ISIL, as well as to protect critical infrastructure, U.S. personnel and facilities, and support humanitarian efforts.

If that sounds like 'mission creep' for an operation sold as an effort to protect Iraqi civilians and Americans in Iraq, then consider President Obama's justification:

In a letter released Sunday notifying Congress of the action, Obama said the militants’ control of the dam posed a threat to the U.S. Embassy 200 miles away in Baghdad, which could be inundated if the dam were breached. “The failure of the Mosul Dam could threaten the lives of large numbers of civilians, endanger U.S. personnel and facilities, including the U.S. Embassy in Baghdad, and prevent the Iraqi government from providing critical services to the Iraqi populace,” he wrote.

Obama had signaled in a statement last week that protecting “critical infrastructure” would be part of what officials have described as a limited military intervention.