An Axios article on Authorizations of Use of Military Force (AUMFs) details some pretty long-standing open season orders, most of them going back to the 20th Century in the Middle East, and Congress’s plan to repeal them, but what’s most interesting in the report is that technically the United States has been at war with France since 1798 and at any time President Biden (and all 44 of his predecessors) can legally order the Navy to open fire on any French flagged vessel. Even more interesting is that later AUMFs – against Tripoli in 1802 and Algeria in 1815 – were repealed by Congress in 1956. This is probably owing to the fact that at that time both were no longer sovereign states and were under French colonial control. Meaning Congress said “Hey these are redundant because they’re all France, so let’s repeal them but leave the main one on the books.”
So, to reiterate, 65 years ago Congress simply tidied up the paperwork on a state of open conflict with France rather than ending it. There is no similar open AUMF for Germany, Japan, North Korea, Vietnam, the Confederate States of America, Mexico, the UK, Spain, Italy, Serbia, Libya, Panama, or any of the other states still in existence or not that the United States has entered into open warfare with in the 223 years since the Washington Administration. Just France.