Sorry, but those scare tactics don’t work for me anymore. No one will stop me from anything even if I remain a practicing and identifying Jew, let alone if I say that I am of no ethnicity and identify myself only by my (non-US second) citizenship.
In the 30’s there was no Internet, no fax machine, no up to the minute communication for people to understand who Hitler was.
Besides, as many assimilated as frum Jews survived the horrors; many of the assimilated ones or the ones who lost their faith in the camps went on to live very successful lives in the US, Canada and even Israel.
Today even a plain old incompetent like Obama is being brought down by mundane Twitter messages among other things. Roosevelt wouldn’t have lasted more than one term today either, nor could he have hid his (physical) disability.