Comment by steve1977

> wouldn't the better solution for airlines to just proactively ban clothing, stickers, etc. with countries' flags, candidate names, political slogans

https://www.united.com/en/us/fly/contract-of-carriage.html

Rule 21 Refusal of Transport

Part H: Safety – Whenever refusal or removal of a Passenger may be necessary for the safety of such Passenger or other Passengers or members of the crew including, but not limited to:

5. Passengers who are barefoot, not properly clothed, or whose clothing is lewd, obscene or offensive;