It's too bad the article didn't say "Using somewhat subjective definitions of "at war"".

"Using somewhat subjective definitions of "at war" -- Korea counts but Kosovo doesn't in our analysis, for example"

How could we be at war? We don't even have a War Department anymore.

Vietnam meets anyone's definition of war.

Debates like these are why international law now tends to speak of 'armed conflict' instead of 'war'.

Certainly the casualty count on both sides makes Vietnam count as a 'war'. And yet, Congress actually declaring a state of war would have given Presidents Kennedy or Johnson vast and sweeping powers, which was something that Congress would be loath to do when the President was already able to kill Commies sufficiently well by simply letting him engage in 'armed conflict' without the state of 'war'.

Except United States' technical definition of war, which must be authroized by Congress.

https://en.wikipedia.org/wiki/Declaration_of_war_by_the_Unit...

> However, that passage provides no specific format for what form legislation must have in order to be considered a "declaration of war" nor does the Constitution itself use this term.

Furthermore, there's no doubt that the U.S. can be at war without an official declaration by Congress: those instances when another country formally declares war on the U.S. first.

For example, the U.S. was officially at war with Japan from 7-8 December 1941, for a few hours with Germany and Italy on 11 December following their declaration of war against the U.S., and from 13 December 1941 to 6 June 1942 against Bulgaria.

https://en.wikipedia.org/wiki/United_States_declaration_of_w...

http://en.wikipedia.org/wiki/United_States_declaration_of_wa...

http://en.wikipedia.org/wiki/United_States_declaration_of_wa...

The American Civil War doesn't count either, then?

It would be rare to see any civil war count as anything other than infighting.

The American Civil War was considered an insurrection by the victor (Lincoln), thus that's what it'll go down as in the history books.

So it's an illegal war. Still a war.

No, Congress explicitly authorized all the conflicts the article is talking about.