I think the real issue is that the military-industrial complex has created the very conditions that lead to massive influxes of "outlanders" in the first place.

Don't want a bunch of people coming in and taking jobs away from those born and raised in any country? Maybe don't destabilize and destroy their homes and create reason for them to emigrate in the first place.

No matter how lenient or strict Customs are, the issue of immigration would be quite minuscule if the State just stopped setting up other states for failure.