You can be banned from the US for any reason, or no reason, just because they don’t like the look of your face, or the officer is having a bad day, etc. Regard

You can be banned from the US for any reason, or no reason, just because they don’t like the look of your face, or the officer is having a bad day, etc. Regardless of what the law says you don’t have any right to enter the US, regardless of what visa you hold (except perhaps a green card), so be friendly, look wealthy and important, and say the right things.