On this date in 1941, the United States declared war on Japan, just one day after the attack on Pearl Harbor. The House vote was 388 to 1 and the vote in the Senate was 88 to zero.  Four years later it was over.  

WWII was our last declaration of war.  The war powers resolution of 1973 was intended to limit presidential power for military engagement  in response to the Vietnam war which in total spread out over 23 years.  It makes it rather easy to start a war but horribly difficult to end it.