This question includes multiple hypotheticals that may have seemed inconceivable a year or two ago, but now that we've shifted to debating about how they might be implemented, consider the following campaign promises of the current US President, which cannot be trivially dismissed:
- "a total and complete shutdown of Muslims entering the United States"
- a registry of Muslims in the United States
Also suppose:
- A US citizen is in that registry as Muslim
- That same citizen travels internationally, e.g. for a conference, business meeting, or tourism
- In version B of the question, the citizen is attempting to re-enter the US from a "terror-prone country" from which entry might be even more restricted.
Can that person be denied entry to the US, if strict policies like those noted above are adopted?
Possibly useful links:
- This question on Final Gear Forums;
- Glenn Greenwald's post about a case where two US citizens were denied re-entry, without court process or criminal charges.