You have absolutely no proof to back up your claims, ie. immigrants don't pay into the school public school system or immigrants are responsible for crime stats.  Actually quite the opposite is true in case of the Vietnam immigrants after the war.  We caused the instability in Iraq, we have a moral obligation to do something about the refugees we created in this war zone.  Germany did not destabilize these region yet they have taken in 1/2 of the refugees we helped create.  We have a moral obligation now, just as we had a moral obligation after the end of the Vietnam war.