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From the notoriously libertarian CATO institute:

President Biden has not suddenly ended America's immigration prohibition and opened up U.S. borders to almost anyone who wants to come (as was largely America's immigration policy from 1776 to 1924). Instead, he has far more vigorously enforced immigration prohibition than the law requires, narrowing the few exceptions to the universal ban on legal immigration.

Like they say on TV, but wait! There's more!

The Biden administration has smashed all records for immediate expulsions without due process, increasing the rate from 62,000 per month under Trump to about 100,000, but Mexico will only take back its own citizens, Guatemalans, Hondurans, and Salvadorans, and even for the Central Americans, it will not take back young kids with their parents if it has no place for them to stay

And, if you act in the next 20 minutes, we'll throw in

Don't believe them? Well, the Trump administration faced the exact same constraints, and they too released many thousands of immigrants from the border. But Biden has a much greater challenge now to keep up his closed border policies. The number of immigrants arriving from outside Mexico and Central America has exploded in the last few months, increasing from about 10,000 to more than 62,000 per month, requiring farther flights and more resources.

It's a complicated problem, but stacking shipping containers which can be cut through with a $99 sawzall from Home Depot isn't among them.

cato.org - Bidens border policy not open borders

I understand that Southern border states have a problem that is overwhelming their resources. Of course Northern states have problems that Southern states don't have, like, oh, snow removal, but nobody asks Arizona to chip in for that to help Vermont. Still, I have to wonder if most countries are protected by a 'Berlin Wall' type thing all along their borders? What do the experiences of, say, Poland and Belgium and Syria and South Africa tell us about land-locked neighbors? I'd really like to know how others handle this problem.

(Obviously ours is greater because of the vast economic disparity between the US and its Southern neighbors. But watching Fox News and radio talk shows for answers are probably the worst possible ways to find out anything truly useful.)