yes, you are very lucky you were shackled and thrown to the ground right there! those people in the immigration hall at jfk are such jerks! never have i found ANY of them pleasant.
oh, and i had my mobile confiscated once, and yelled at another time--note, i wasnt actually ON
the phone, i pulled it out to check the time--which is not prohibited, as only being ON
the phone is. so i had to argue that both times to keep my phone.