The war powers act (1973) was an attempt by congress to

The War Powers Act, also known as the War Powers Resolution of 1973, requires the following: the President, upon sending troops into military action, must notify Congress within 48 hours that he has done so. The Resolution also forbids military personnel from remaining in a state of conflict for more than 60 days (including an additional 30 days for withdrawal). After that, the President must seek an additional authorization from Congress or a formal declaration of war.

So, you may ask, how was war declared prior to 1973? For an answer to that question, we'll have to look back at some prior conflicts and at the U. S. Constitution.