FDR did not want war but perhaps handled things in such a way to make it inevitable we would be involved in what he hoped would stay a European war. The Americans and Japanese were working on a peace treaty and were coming to the end of what would hopefully be successful negotiations when Pearl Harbor was attacked. Japanese personnel were at their embassy in Washington DC and our embassy in Tokyo was fully staffed and operating normally when the attack occurred.
FDR had declined pleas from England for help staving off German attacks and did not want America to become involved. But he did not rule out passive help or object when a number of American aviators went to England to reinforce the RAF when Germany was repeatedly attacking England. As a precaution though, as of September 1941, our military had orders to fire on any German warship approaching the U.S. coast that did not turn around when ordered to do so. At the same time we had a fully staffed and active embassy in Germany and they in Washington DC until the Japanese attacked Pearl Harbor in December 1941. When we declared war on Japan as a result of that attack, Germany who was allied with Japan then declared war on us. We had no choice but to reciprocate and what was then relabeled WWII was on.