TSA answers question about hijabs / head scarves for women visiting USA
Safety should be a key consideration no matter where you travel, and part of staying safe in an unfamiliar place is dressing to blend in — or, at least, not dressing to stand out. Please keep in mind local customs and attitudes, as well as religious beliefs, when choosing your attire. Dressing like a tourist, not a terrorist, will help you avoid causing offense to locals or becoming a target.
We encourage people to have the appropriate expectations when they arrive at U.S. airports. Contemplate increased wait times if you travel wearing hijabs and/or head scarves.