Lotta people on this forum think he's a tuff guy but all I see is a blustering loudmouth, always spoiling for a fight in some irrelevant buttsore of a country, probably where one of his friends owns a ranch.
Only the Congress has the power to declare war. That was put in the Constitution by men who knew that Kings were always looking to use the citizenry as fodder for some fight that would benefit the King and his buddies. Those who don't want to be fodder are supposedly represented in the Congress. Thus the requirement.
The War Powers Act of 1973 codifies what the President can do without Congress. It is power they ceded to him to be practical - things happen that supposedly just can't wait. But this one can.
Thanks for link on War Powers Act.