Just proof they should have prevented them from coming in the first place.
Allowing all these people in to the US is racist against those other countries, we are robbing them of their people and their intellect. How are these countries ever going to thrive without their people?
I don't know if this is still the case, but the Dominican Republic used to restrict Visas for citizens, in that whole families were not issued visas. For example, we have a friend who travelled to the US quite frequently, but was not allowed to bring his children, as the country wanted him to have incentive to return.