Let me quote this:
“ Provides that in the absence of a declaration of war by the Congress, in any case in which the Armed Forces of the United States are introduced in hostilities, or in situations where imminent involvement in hostilities is clearly indicated by the circumstances, such use of the Armed Forces of the United States in hostilities pursuant to this Act shall be reported within 48 hours in writing by the President to the Speaker of the House of Representatives and the President pro tempore of the Senate, together with a full account of the circumstances under which such hostilities were initiated, the estimated scope and duration of such hostilities, and the constitutional and legislative authority under which the introduction of hostilities took place.”
Source: (aka The War Powers Resilution)
https://www.congress.gov/bill/93rd-congress/house-joint-resolution/542
See also: The United States Constitution, Article II, Section 2.1
The constitution gives the authority to the president to command the armed forces. The constitution gives the authority to the legislature to declare war. Any discrepancies between the two have not been adjudicated by the Supreme Court, the third branch of the government.
Historical precedent is that the Commander in Chief has ordered the military to take actions without a declaration of war. One of these was FDR sending the Navy to fight the Nazis by defending merchant marine convoys to England before war was declared against Germany.
The last formal declaration of war was against Bulgaria, Hungary and Romania, in conjunction with the war against Japan, Germany and Italy. Correct.
But the year was 1942, 84 years ago.
