This comment is devoid of data. There have been less stoppages and detentions than you can count on one hand of scientists and mathematicians. There are hundreds of thousands classified via various levels of visa. None have been arrested in some unlawful manner, and the onus is on you to define "asshattery" in a way that is defensible. Foreign adversaries have been embedded within the US academic institutions before the Cold War. Just because the current US president is a divisive convicted felon doesn't suddenly mean we shouldn't care about controlling our own borders.
The US (and many nations for that matter) monitor, track, and protect their borders by foreigners and of a group of mathematicians cannot fathom why this may be the case amidst all-time high mistrust, spying, and academic and corporate espionage and then they should've studied harder.
The US (and many nations for that matter) monitor, track, and protect their borders by foreigners and of a group of mathematicians cannot fathom why this may be the case amidst all-time high mistrust, spying, and academic and corporate espionage and then they should've studied harder.