Donald Trump's Executive Order on immigration is unprecedented.
False. Barack Obama stopped immigration from Iraq for six months. Jimmy Carter stopped it from Iran during the 444 day hostage crisis. Trump's order returns refugee admitance to pre-2016 levels.
blah blah blah Japanese internment camps during World War 2 blah blah
First, not relevant here. Second, that was done by FDR, a democrat. Third, 38% of those interned were NON-American citizens. Most of the rest were there to keep families together.
But the constitutionality of Executive Order 9066 was challenged and the case made it all the way to the Supreme Court.
Which refused to hear the case for the very pragmatic reason that the nation might need to do a similar thing again someday, and they did not want to tie a future president's hands.