The Constitution delegates to Congress very specific duties concerning the armed forces of the United States. Not one of them involves conducting the affairs of war.
Article I, Section 8 defines the powers of Congress with regard to the armed forces, and directing a war effort is not there.
Article II, Section 2 states unequivocally that "The President shall be Commander in Chief of the Army and Navy of the United States, and of the Militia of the several States, when called into the actual Service of the United States."
Maybe it's time that the defeatist cabal in Congress be reminded of that, if they even knew it to begin with.