When the Pentagon was authorized by Congress BEFORE America joined WWII under the last Roosevelt Administration, it makes you wonder if he thought he could resist London's Zionist Demands.
He apparently refused a ship of jewish refugees escaping persecution in 1939 - history.com says it was the the S.S. St. Louis https://www.history.com/this-day-in-history/ss-st-louis-jewish-refugees-t..
The Smithsonian reports the US was justified in 1942 with this report
https://www.smithsonianmag.com/history/us-government-turned-away-t..