The War Powers Act of 1973 gives him 60 days to seek approval from the House or withdraw the troops.
In this one regard, he has done nothing unconstitutional.
“...he has done nothing unconstitutional.”
The act of ordering military action with circumstances that the US, nor US interests were attacked initially is unconstitutional.
He used the excuse of a UN resolution.
That resolution belonged to the US Congress to debate, and authorize any action, NOT the President.