20-Year Prospect

20-Year Prospect

The U.S. borders are very long, and building a wall that big has never been a solid idea. The whole idea of using walls to keep people out is a pretty medieval concept anyway. It also isn't very cost-effective; building Soviet-style heavy-duty concrete walls and electrified fences—complete with patrolling guard dogs, flood lights, and barbed wire—across thousands of miles would be ridiculously expensive.

This means that it's likely that the actual job of patrolling the national ports of entry won't change much in the coming decades. Uncle Sam will count on Customs agents to keep order on the border as long as we haven't actually conquered the entire globe.

Two things that will change are technological advances and laws, and both of those depend a lot more on the people inside America rather than outside. 

Technological advances will make it easier to process immigrants, conduct identification screenings, and scan for drugs and weapons. Laws will be written and rewritten that will define (and redefine) what an immigrant is—and people will probably still be fighting over it in the years to come.