They allow pretty much all Jews to immigrate freely. As I said, they are trying to make the place homogenous. When I was there, it was against the law for Jews to marry non-Jews in the country, although they would recognize such marriages if they were recognized by a foreign country, so to get around the law people would travel to somewhere like Cyprus to get married. It was like an apartheid state there.
But since you brought up homogeneity as a factor in how countries should treat their citizens, why don't you elaborate on that for us?