AMNA NAWAZ: A standoff between federal Border Patrol and Texas state officials is intensifying following a Supreme Court ruling in favor of the Biden administration.

Laura Barron-Lopez has more.

LAURA BARRON-LOPEZ: Earlier this week, the Supreme Court said U.S. Border Patrol agents could remove razor wire that the state put in place along the Rio Grande River.

The Homeland Security Department is demanding immediate access to a section of the border and being blocked with razor wire and fencing.

But Texas Governor Greg Abbott is doubling down, blocking the agents from entering the area and saying Texas constitutional authority is -- quote -- "the supreme law of the land and supersedes any federal statutes to the contrary."

Joining me to discuss this further is Stephen Vladeck, a professor at the University of Texas School of Law.

Professor Vladeck, thanks so much for joining.

Republican Governor Abbott is saying Texas is going to hold the line.

And it's unclear when or if this razor wire is going to be removed.

Who ultimately has the authority over the border here?

STEPHEN VLADECK, University of Texas School of Law: Yes, I mean, I think it's pretty clear, under the Constitution, under our precedents, that immigration policy, control of the border really is ultimately in the federal government's purview.

But, Laura, I think it's just as clear that Governor Abbott wants this confrontation and that he's willing to take this battle all the way back to the Supreme Court before he's going to stand down.

LAURA BARRON-LOPEZ: And Governor Abbott is claiming that he has this authority under the U.S. Constitution because the federal government isn't protecting Texas against a -- quote -- "invasion."

That's the way he's been describing it.

Is this a reasonable interpretation of the Constitution?

STEVE VLADECK: No, and in two different respects.

I mean, the first is that, obviously, an influx of asylum seekers, however many we're talking about, is not what the founders had in mind when they used the word invasion.

But, Laura, second, even if you're not persuaded by that, the clause Governor Abbott's relying on in Article 1, Section 10 of the Constitution was dealing with the specific scenario of the ability of states to respond to invasions until federal authorities were able to respond.

This is the time in American history when the federal military was small.

It was very spread out.

It took weeks to travel.

Congress was usually out of session.

There's no support in our history, there's no support in founding or other materials for the idea that states can decide for themselves that they're under invasion, and, even if the federal government disagrees, that somehow it's the state's determination that would control.

LAURA BARRON-LOPEZ: Recently, three migrants drowned in the Rio Grande in this section that Border Patrol agents have been trying to access.

And all this comes as a number of Republican governors still say that they support Texas, that they stand by Texas.

What are the larger implications of this standoff between Texas and the federal government?

STEVE VLADECK: I mean, the larger implications are pretty staggering.

It's not just the specter of a physical confrontation between federal and Texas officials along the border in Eagle Pass.

It's also basically a relegation of a debate that we had in American law for the first 70 years of this country about the ability of states to effectively nullify those federal laws that they disagreed with, that they thought were unconstitutional.

For better or for worse in our constitutional system, federal law supersedes state law, even when we don't like how the federal government is or is not enforcing those federal laws.

The remedies for those disagreements are not to allow every state to go out on their own and to have their own policies.

The remedies, if you really have a problem with the policies, is to change the people who are making them.

Otherwise, it's a federal system, Laura, in name only.

LAURA BARRON-LOPEZ: And Governor Abbott also claims that the federal government has -- quote -- "broken the compact with states."

Where have -- what do you think he means by that?

And have states in the past used that language to justify defying the federal government?

STEVE VLADECK: Yes, I mean, the compact theory of the Constitution is a pretty outlier view, especially these days, about the way the Constitution was formed.

The basic premise is that the federal government, the constitutional system we have was formed by the states, and, therefore, the states can control its terms.

That was the argument on which the Southern states predicated secession and helped to precipitate the Civil War.

There's a reason why we tend not to hear that much of it these days.

Again, I mean, I think there's a lot of folks who are going to have strong views about whether the Biden administration is or isn't doing what's best for the country at the border.

But the way to air those disagreements is through the federal electoral process.

In a world in which states can follow this version of the compact theory as a justification for interfering with federal authority, what's to stop California from doing that to the next Republican president?

What's to stop Vermont from doing that to the next Republican president?

And then we're talking about a system in which the states have all the power, and the federal government is basically impotent to do anything.

LAURA BARRON-LOPEZ: Professor Stephen Vladeck of the University of Texas, thank you for your time.

STEVE VLADECK: Thank you.