Fortunately for us the Germans were stupid. They chose to murder all of the relatives of those immigrants for ideological reasons instead of using their safety

Fortunately for us the Germans were stupid. They chose to murder all of the relatives of those immigrants for ideological reasons instead of using their safety and life as leverage to influence the behavior of the emigres in important scientific positions. The Chinese are known to do exactly this and I don't expect too many students or professors to put their adoptive country over family.