I am trying to locate a short story about a new radar being tested by the US Navy during WWII. The captain of the test vessel encounters a Japanese fleet heading to the west coast and using the new radar was able to defeat the convoy. I remember at the end the president, unprepared for the invasion, asked for the captain to surrender and the captain's reply was something like, who should I surrender to.
As noted in the answer to this question, this seems to be "Politics" by Murray Leinster. The story points up how technology (the new radar, tied to gun training computers) can affect politics. Originally published in Amazing in June, 1932 (available for free at the Internet Archive), it was (as far as I can find) last printed in 18 Greatest Science Fiction Stories, from Tempo, 1971.