On Tuesday, I filed a brief urging the Supreme Court to uphold President Donald Trump’s executive order temporarily pausing the entry of foreign nationals from six terror-prone counties.

Supreme Court review is needed because the U.S. Court of Appeals for the 4th Circuit recently ruled against the valid executive order. I am leading a multistate coalition asking the Supreme Court to permit the president to exercise his lawful authority to protect the homeland.

What the 4th Circuit completely missed is that the executive order is a tailored response to a very real threat to our national security.

A pause on entry from countries with heightened security concerns—such as Libya, where authorities arrested suspects linked to the horrific attack in Manchester—is justified to ensure that new arrivals are thoroughly vetted.

Liberal activists are upset that Trump is keeping his promise to secure our border, protect our country, and keep Americans safe from acts of terror.

Unfortunately, it seems that some federal judges, like the majority of the court that opined against the president’s executive order, are now substituting their “politically desired outcome” for the law, to quote dissenting Judge Paul Niemeyer.

The multistate brief that I filed shows courts have long recognized that the federal government has the power to exclude aliens.

In fact, the U.S. Supreme Court has repeatedly described the ability to refuse the admission of aliens into our country as a core federal prerogative, which is “inherent in sovereignty” and necessary “for defending the country against foreign encroachments and dangers.”

Moreover, Congress clearly vests the executive branch with the statutory authority to exclude aliens.

8 U.S.C. § 1182 authorizes the president to “suspend the entry of all aliens or any class of aliens as immigrants or nonimmigrants, or impose on the entry of aliens any restrictions which he may deem to be appropriate.”

There are many prior incidents of administrations barring entry of aliens based on their nationality. Democratic Presidents Bill Clinton and Barack Obama used the exact same statutory authority claimed by Trump to refuse admission to aliens from Sudan, Sierra Leone, Venezuela, and Libya.

Federal law makes it plain that the power to exclude is subject only to the president’s finding “that the entry of any aliens or of any class of aliens into the United States would be detrimental to the interests of the United States.”

That requirement is easily met here. Indeed, the Obama administration previously identified the six countries covered by the Trump executive order as national security concerns.

It is equally clear under Supreme Court precedent that courts have no business overriding the president’s use of full federal authority to deny classes of nonresident aliens into the United States.

Simply put, nonresident aliens who have never set foot on American soil do not possess rights under the United States Constitution regarding entry into this country.

The president’s predecessor had years to strengthen the vetting process. He failed to do so and therefore opened the United States to the types of attacks executed in Germany, France, Belgium, and England.

Had Obama taken the threat seriously, the temporary pause in entry called for in the executive order may not have been necessary.

For years, Texas has been concerned about refugees and immigrants coming into the state from countries whose governments are official sponsors of terrorism. We asked our federal government for information so that Texans were not left in the dark about the individuals placed in our neighborhoods.

But our pleas to the Obama administration to ensure proper vetting fell on deaf ears.

We finally have a president who is serious about securing our borders and keeping Americans safe. It is widely accepted that terrorist attacks are the product of networks that stretch across borders.

Trump’s executive order on foreign entry will allow the time necessary to shore up our nation’s screening procedures and help prevent bloodthirsty extremists, like those who aided and abetted the attacks in Manchester, from infiltrating our homeland.

Trump promised in his oath of office to protect our democracy. His travel ban delivers on that promise. As attorney general of Texas, I fully support his administration’s commitment to defend this action all the way to the Supreme Court.