>>507869446 (OP)In America to declare war you need Congressional support but thanks to the AUMF a President can initiate any "military action" he wants so long as it can cite "terrorism" as its impetus. As long as the troops sent are kept under 25k bodies, they never have to go to Congress about it.
https://www.congress.gov/107/plaws/publ40/PLAW-107publ40.pdf
Obviously this is a lot more convenient for the Executive Branch.