For the most part Presidents have ignored the War Powers Act partly on the grounds that it is Unconstitutional for one branch of government to either increase or decrease the power of another branch. separation of power
The War Powers Resolution was passed in 1973. It was designed to limit the president's power to commit U.S. troops abroad without congressional approval.
it limits the president's power to wage war-for example:congress never declared war in Korea and Vietnam... yet the United States became involved on armed conflict in Korea after president Trumen...