Why USS Reuben James did not trigger war

Why did the loss of USS Reuben James not lead to a US declaration of war on Germany, and would Pearl Harbor still have happened?

The proposed explanation is that Roosevelt lacked the congressional support, or would have paid too high a political price, while Japan's decision to attack followed its own strategic calculation.

USS Reuben James was an old Clemson-class destroyer escorting an Atlantic convoy when a U-boat torpedo sank her. The incident followed other clashes between American destroyers and German submarines, but these patrols were already stretching the practical meaning of neutrality. The president could not declare war alone, and one explanation offered is that Roosevelt lacked enough congressional support to obtain a declaration over the loss. On that interpretation, forcing the issue would consume political capital and might curtail the assistance already being delivered to Britain. Pearl Harbor remained driven by Japan's separate strategic decision, and Hitler's later declaration ultimately removed Roosevelt's political problem.