The St. Louis, denied entry at the port of Miami, turned back for Europe. About a third of its passengers ended up in Great Britain, while the rest were sprinkled throughout Western Europe, aka "the place where the Nazis were." By June of 1940, FDR had drunk deep of the Conspiracy Kool-Aid, stating: "Now, of course, the refugee has got to be checked because, unfortunately, among the refugees there are some spies, as has been found in other countries. And not all of them are voluntary spies -- it is rather a horrible story but in some of the other countries that refugees out of Germany have gone to, especially Jewish refugees, they found a number of definitely proven spies."
And by golly, he was right: In 1942, the United States convicted Herbert Karl Friedrich Bahr of being a Nazi spy posing as a Jewish refugee -- the single known instance of such a thing happening. Of the 937 passengers aboard the St. Louis, 254 died in the Holocaust. In 1945, Cordell Hull was awarded the Nobel Peace Prize. Karma's a lovely idea, isn't it?