Japan had a naval force that could strike pretty much anywhere in the Pacific and Indian Ocean. Hawaii is but one speck in that vast expanse of potential targets.
The whereabouts of the Japanese carrier force was unknown,
Incorrect. Through masterful radio deception, the Japanese main fleet was believed by U.S. intelligence to be in home waters.
which should have put us on a heightened alert
U.S. forces in Hawaii had recently been on high alert. U.S. forces in the Philippines were on high alert. MacArthur had all available aircraft in the air but the timing was a few hours off. The Japanese struck the airfields after the planes returned to base to refuel.
FDR, Marshall, et al. were welcoming an attack.
That FDR was seeking a way to join the war in Europe is no secret. The Japanese were of secondary concern to FDR.
FDR was truly upset when he gave his “day of infamy” speech because he didn't think that the attack would cripple us so. He was rarely double crossed and was pissed off! It was FDR's saying, “In politics, nothing happens by accident”.
If FDR was pissed, it was most likely because with ample indication of imminent hostilities, U.S. commanders at Pearl allowed themselves to be so unprepared.
Read “At Dawn We Slept”, the commission blamed the Army and the Navy (Admirals and Generals are expendable)but never even mentioned the White House. My guess is that it was a set up to put the blame in Hawaii.
The only ones surprised by the attack were U.S. commanders at Pearl harbor.
Read the book and my following post re my uncle.