Article I, Section 8, Clause 11 of the United States Constitution, sometimes referred to as the War Powers Clause, exclusively vests in Congress the power to declare war. However, in a Representative Democracy, Congress should ultimately represent/abide to the will of the People; therefore it is proper to request a national referendum asking for the CONSENT of the American People before Congress authorizes war powers to the Commander-in-Chief or the deployment of military force/personnel against Syria.
"We should take nothing for granted. Only an alert and knowledgeable citizenry can compel the proper meshing of the huge industrial and military machinery of defense with our peaceful methods and goals, so that security and liberty may prosper together." -Dwight D. Eisenhower, 1961.