General Discussion

But Congress isn't interested in taking back the need to declare war. Partially for good reasons, partially for bad reasons.

The good reason being for some small scale actions, speed and secrecy is critical. For example Ford used the military to rescue the crew of a boat that had been captured by the Cambodian navy. Waiting to get Congressional approval would have let the victims be better secured. Or Obama making the decision to conduct the bin Laden raid into a sovereign country.

Obviously those are pretty limited circumstances where that matters, and as the kidnapping of Maduro shows it can easily be misused.

Then there's the bad reasons that Congress won't repeal it. They don't have to go on the record in case something goes wrong, and it gives them a great way to attack a president of the other party. Republicans attacked Obama for his use of the military without congressional approval for drone and missile attacks and now we're doing it to Trump. I'm not saying that the two situations are equal in their level, but if the principle is about Congress having to declare war, then they are both wrong.

But Congress is also hard pressed to take back their power because it's a lot harder to get a majority out of the 535 members of Congress compared to the president needing to decide their position. This is more true as government becomes more complex and as partisanship increases making it easier to shift responsibility to the president or the administrative state.