

Due to the invasiveness of the procedure, I don’t imagine the current administration would find much use for it.
Or: “All Liberals must undergo an American Loyalty Test. Your thoughts will be observed and if any anti-american sentiment is discovered you will be deported!”
If it’s used against an “enemy” group the invasiveness (potential pain) would be viewed as a benefit to them.
Not that I think this could be reasonably carried out in a country of 400 million people, but I wouldn’t for one second doubt their willingness to try eventually.
“Anything that says Hitler was bad, slavery was bad, and that Donald Trump isn’t literally God is biased and must be changed!”