“We’ve got incredible experience at building partners and building military and police formations," Dempsey said, referring to U.S.-led advise and assist missions in Iraq, Afghanistan and elsewhere.
While Dempsey did not provide specifics on a possible American-led military training mission in Syria, U.S. forces would likely focus their efforts on the Free Syrian Army (FSA).
The group is considered the largest and best organized faction among the patchwork group of rebel fighters in the country.
In September, U.S. intelligence officials began funeling small arms and munitions to Syrian rebel forces, including the FSA.
President Obama ordered the CIA to begin setting up distribution points in Jordan and Turkey to start providing American arms to rebel forces in June.
However, security assistance operations in preparation for a post-Assad Syria is a "valid concept to be thinking about," particularly as Damascus continues with a disarmament plan for its chemical weapons arsenal, Dempsey said.
The United Nations Security Council approved a resolution last month requiring the Assad regime to turn over its arsenal to the international community.
The resolution calls for Syria's estimated 1,000-tin stockpile to be scrapped by mid-2014.
On Wednesday, the international team charged with collecting and destroying Syria's chemical weapons wrapped up its first day of work inside Syria without incident.
Even if the Assad regime fully complies with the disarmament plan, Pentagon-led efforts to school a new Syrian security force would go against the department's pledge of no U.S. boots on the ground in the country.
American military leaders will also have to find a way to weed out Islamic extremist groups from becoming part of a Syrian security force, if a U.S. training program is given the green light.
The State Department estimates that Islamic militants, such as Jabhat al Nusra (JAN) and the al Qaeda-linked Islamic State of Iraq and Syria, make up less than 20 percent of the Syrian opposition.
However, Pentagon officials estimate that extreme Islamist groups now constitute over 50 percent of the rebel force, with that number growing as the civil war enters its third year.