1) Fine. Let's flip this: if rich white people were coming into this country from Canada seeking even more wealth, and tended to vote Republican, would you and your liberal friends be so keen to defend the rights of illegal--excuse me "undocumented" immigrants? What would happen if I went to Mexico without proper "documentation?"  Have you ever read their constitution? Is their constitution racist because it does not allow for illegal--excuse me "undocumented" immigrants?  

2) I don't think our Lord intends to suggest that countries do not have the right to sovereignty or to set the parameters on who can and cannot come into the country.  In fact, I dare say that our Lord knows full well that open border policy would quickly lead to a nations destruction. 

3) So what? What does that have to do with anything? It is a prudential judgement--and therefore does not have the same moral weight.