"I think Democrats and a few Republicans have absolutely no clue as to the threats that we face," the South Carolina Republican said Tuesday, according to The Hill.
"We're going to get attacked from Syria. That's where the next 9/11 is coming from. After that happens, and I pray that I'm wrong, everybody will take a different view," Graham, a presidential candidate for 2016, added.
Senator Chris Murphy, Democrat of Connecticut, said there were still "irreconcilable differences” between Republicans and Democrats in Congress over authorization for the use of military force in Syria.
President Barack Obama’s decision to deploy dozens of Special Operations forces to Syria to "advise” US-backed militants on the ground has reignited the long-stalled debate on authorizing the war.
"It doesn't appear to have changed the disposition of the Foreign Relations Committee, yet,” Sen. Murphy told reported on Tuesday.
Congressional lawmakers have struggled for months to overcome divisions on legislation authorizing the war against ISIL, which started last August when the US and its allies launched an air campaign in Iraq and a month later in neighboring Syria.
The issue has widened splits between and within the Republican and Democratic parties.
Chairman of the Foreign Relations Committee, Senator Bob Corker, argued Tuesday that a new war bill was not needed.
"As I've said from the beginning, I believe the administration has the authorities to do what they're doing against ISIS,” the Tennessee Republican said, using another acronym for the terror network.
The senator added that sending in special forces does not change that.
The deployment comes amid Russia’s intensifying air campaign in the country to assist President Bashar al-Assad in the fight against ISIL.
Syria has been gripped by foreign-backed militancy since March 2011. The crisis has claimed the lives of more than 250,000 people so far and displaced millions of others.