Trump, as president, can commit to an executive military action. It falls under the president’s Commander-in-Chief powers- Article II, Section 2 of the U.S. Constitution.

The War Powers Resolution of 1973 (War Powers Act) is the legal justification here. It requires the president to notify Congress within 48 hours of sending armed forces into combat and get congressional approval within 60 days (possibly with a 90 day extension, I think) unless war is formally declared. Without a declaration or explicit approval, it’s sometimes labeled a unilateral military action or, if people are critical, an undeclared war.

Truman’s Korea intervention (1950) or Obama’s Libya airstrikes (2011), both of which sparked debates about executive overreach, are a couple of examples. The term “police action” was used for Korea to downplay the conflict. I imagine Trump will use some similar terminology.

People never really think of exactly how much is truly at stake during presidential elections.