Senators Tim Kaine of Virginia and Jeff Flake of Arizona have pushed their colleagues to require Congressional authorization for use of force overseas. They are so right.

In the wake of the deaths of four American soldiers in Niger, many Americans, including some lawmakers on Sunday’s talk show circuit, are asking what the United States is doing in West Africa (answer: 800 troops are said to be helping Nigeriens combat terrorism) and under what authority they are there.

Good questions. Perhaps the feedback to these deaths will provide some backing from his colleagues of Kaine’s quest. ...