Many Constitutional rights apply to citizens and non-citizens alike, for the simple reason that the Constitution (and specifically the bill of rights) does not create or grant rights, but simply protects those rights from intrusion by the government.
It may be the case that the Constitution does not protect certain rights (perhaps even the Second Amendment rights) of non-citizens, but it is not accurate to flatly state that Constitutional rights do not apply to non-citizens.
In my book, the Constitution is not for non-citizens....we differ. (In the vernacular of the common liberal, I’ve interpreted this meaning as a ‘living document” transtional definition specifically relating to our current time where foreigners are a threat to us).....