I don't think I said anything about a "wall."  But, Diversity and tolerance are not to be seen in a vacuum.  For example, I will never tolerate someone's child throwing rocks at my child or any number of other things. I also see no reason for people to remain in "sub groups" for diversity reasons.  While your heritage may be Scandinavian or S. African should not matter for any reason!  The only reason we have that word now is so that people can access unequally various gov't porgrams and monies!   And, America is a "melting pot" not a country made up of distinct, diverse populations.  Even Teddy Roosevelt stated as President that unless someone wants to come to America to become an American, he/she is not welcome! 
There is nothing in our Constitution which states that the U.S. will allow anyone at any time who wants in to come in!  Every President since late 1800's had bans.  The last 5 presidents including Clinton all had similar bans as Trump's!  And none of them ban "Muslims!"