REUTERS/Kevin Lamarque
U.S. Secretary of Defense Chuck Hagel (L) and Chairman of the Joint Chiefs of Staff General Martin Dempsey testify during the Senate Armed Services Committee hearing on the U.S. policy toward Iraq and Syria and the threat posed by the Islamic State.
"As was clear from General Dempsey's remarks, he was referring to a hypothetical scenario in which there might be a future situation in which he might make a tactical recommendation to the president as it relates to ... the use of ground troops," White House press secretary Josh Earnest told reporters aboard Air Force One on Tuesday, according to a pool report.
Gen. Martin Dempsey, the chairman of the joint chiefs of staff, told a Senate panel earlier Tuesday that he would advise Obama to use ground troops in the US mission against the Islamic State (also known as ISIS or ISIL) if the extremist group evolves into a threat against the US homeland while the current strategy fails.
He also said he might advise Obama to aid the Iraqi Security Forces in certain theoretical missions. For example, one theoretical mission in which he suggested US military advisers currently in Iraq join the ISF to retake Iraq's second-largest city of Mosul.
"To be clear, if we reach the point where I believe our advisers should accompany Iraqi troops on attacks against specific ISIL targets, I will recommend that to the president," Dempsey said in testimony before the Senate Armed Services Committee.
"My view at this point is that this coalition is the appropriate way forward," he added. "I believe that will prove true. If it fails to be true and there are threats to the US, then of course I would go back to the president and make the recommendation that may include the use of U.S. military ground forces."
REUTERS/Jonathan Ernst U.S. President Barack Obama (L-R) is greeted by Chairman of the Joint Chiefs of Staff U.S. Army General Martin Dempsey and U.S. Defense Secretary Chuck Hagel as he takes the stage for remarks at the Memorial Day observances at Arlington National Cemetery in Arlington, Virginia, May 27, 2013. 
Dempsey's comments ran contrary to what Obama has said repeatedly over the past few months - that American ground troops won't have a combat role in Iraq.
During a primetime speech from the White House last Wednesday when he laid out his strategy, Obama said US airstrikes on the group would support partners on the ground, including the Iraqi Security Forces and moderate rebels fighting ISIS in Syria.
"I want the American people to understand how this effort will be different from the wars in Iraq and Afghanistan," Obama said. "It will not involve American combat troops fighting on foreign soil. This counterterrorism campaign will be waged through a steady, relentless effort to take out ISIL wherever they exist, using our air power and our support for partner forces on the ground."
The US went on offense with Iraqi forces against ISIS for the first time Monday night as part of its expanded mission against the group, striking a target southwest of Baghdad. US airstrikes are expected to ramp up in both Iraq and, eventually, in Syria, where it will work with rebels of the Free Syrian Army.
The House of Representatives is expected to soon pass legislation that would give Obama the authority to train and equip the rebels in Syria. Both Hagel and Dempsey said the US was prepared to conduct airstrikes in Syria.
"This will not look like 'shock and awe' because that is not how ISIL is organized," Dempsey said, referring to the start of the 2003 campaign in Iraq. "But it will be persistent and sustainable."