He should not be allowed to do so -- not because of any American hostility to the Koran, but because the act undermines American civilization Like it makes one iota of difference.
Unless the author is so delusional he thinks those who have taken oaths with the Bible have never, ever engaged in fraud, deception, theft, etc, etc.
LOL -- the way 99% of Congresscritters behave, they should swear them in on a copy of Police Gazette.