U.S. congressional leaders to receive Syria briefing on Thursday

[freshwest]

4. The two sentences in the law seem to contradict each other to me, a lay person:

Under the 1973 U.S. War Powers Act, the president must notify lawmakers within 48 hours of launching military action.

Okay, no problemo. He is doing that.

But forces can fight for 60 days before Congress has to approve any action.

60 days, starting when? Right after the briefing, or before the briefing?
Why not get approval or a declaration of war? And have we ever really had one since then? Or was that only a formality throughout history?

The 1973 War Powers Act was a Nixon-era law, not sure that there was a good reason for it. The Vietnam War was close to ending at that time.

Or was it a limit on what previous presidents had done with some actions around the world?

Like to hear from better informed members, such as veterans or currently enlisted folks. TIA.