A "police action" was another American name for a war that Congress hadn't officially declared, although the funding was certainly there. Examples from around the globe where 20th Century American "police actions" took place were Korea, Vietnam, Lebanon, Nicaragua, Bosnia and Somalia.
When accused of waging war by the world press, the Pentagon would often use the word "police action". When accused of a "police action", the Pentagon would then use the term "military advisers", knowing full well that no one would jump on a General's back or even a President's back for offering another country a little "free advice".