Four senators called the civil war "the world's worst humanitarian crisis in recent times."
Obama reportedly also foresaw the ISIS conflict as a long-term battle.
Opposition suffers at hands of Assad and ISIS while U.S.-led training fails to materialize.
Josh Earnest said Syria's intervention was not "the solution to the threat confronting Iraq."
Sen. John McCain said the conflict in Syria would eventually affect the United States.
The administration ordered Syria to suspend all diplomatic operations in the U.S.
Negotiations backed by the U.S. and Russia will take place on Jan. 22.
Lawmakers who went out on a limb to support strikes tore into Robert Ford.
“There's no dialogue, there's – let's say, information – but there's no dialogue,” Assad said.
The U.S. has neutralized nearly 600 tons of Assad's lethal chemical agents.
Members of the House Armed Services Committee want more specifics from Obama.
A U.N.-affiliated team was unable to reach the location of a reported chlorine gas strike.
A British diplomat warned Thursday that Syria has not turned over the last of its chemical weapons...
Kerry admitted "it's fair to say that Assad" could now seem more legitimate.
The comments could anger groups calling for Assad's ouster as a precondition.