Comparisons to Americans of German descent fighting for the Nazis aren't relevant to this discussion, in my opinion. This guy was killed in
Yemen -- a country that is not formally at war against the U.S.
If aiding and abetting an undeclared "enemy" is sufficient cause for the U.S. government to take this kind of action, then I fail to see how Jane Fonda can go about her business freely in this country to this very day.
Comparisons to Americans of German descent fighting for the Nazis aren't relevant to this discussion, in my opinion. This guy was killed in Yemen -- a country that is not formally at war against the U.S. Would it change your opinion if the summary executions that Seruzawa spoke of happened in, say, Ardenne France?