At long last, the full 4th U.S. Circuit Court of Appeals today issued its ruling in IAAB v. Trump, the challenge brought by Americans United and its allies to the current iteration of President Donald Trump’s Muslim ban.

As we hoped, the court ruled in our favor, agreeing with us that the ban likely violates the Constitution because of the strong evidence that President Donald Trump’s purpose was to exclude Muslims from the United States.

But it may feel like Groundhog Day to faithful readers of this blog.  Trump’s Muslim ban, in one form or another, has been litigated up and down the courts all around the country for more than a year now. And indeed, the courts have repeatedly blocked it for one reason or another, including for violating the First Amendment’s promise of governmental neutrality toward religion.

So rather than recite once more the gross litany of anti-Muslim statements that Trump has made or rehash the many ways that the ban violates the Constitution, let’s talk about what’s different this time.

The majority of the 4th Circuit declared that the ban is “not only a likely Establishment Clause violation, but also strikes at the basic notion that the government may not act based on ‘religious animosity.’”

Today was the first time that a federal court of appeals ruled that the current version of the ban, released in September, is a Muslim ban – and  thus that it violates the Constitution by targeting Muslims for disfavor. Another court of appeals – the  9th U.S. Circuit Court of Appeals – previously  ruled that the ban could not stand, but on different grounds; that court determined that the ban violates our country’s immigration laws. But today’s majority opinion, written by Chief Judge Roger Gregory on behalf of a nine-judge majority, decides the constitutional question. (Five judges on the 4th Circuit in today’s decision believe that the ban also violates the immigration laws.)

That the court today ruled on the constitutional question matters for a couple of reasons. First, the Supreme Court has already decided to review the 9th Circuit’s decision and thus is expected to issue an opinion by late June on the legality of the Muslim ban. And though the court stated that it would consider not only whether the Muslim ban violates the immigration laws but also whether it violates the First Amendment’s Establishment Clause – the  part of the Constitution that prevents the government from favoring certain religions over others, or all religions over none – until  today, the high court wouldn’t have had the benefit of a well-reasoned appellate decision explaining how  Trump’s actions trample that critical constitutional protection of religious freedom.

And second, as Judge Pamela Harris pointed out today in a concurring opinion, the Muslim ban is an “extraordinary” case. Most often, church-state  cases center on governmental favoritism toward a particular faith or toward religion generally, both of which are, of course, unconstitutional. But the Muslim ban is the other side of the coin: The president acted “on the basis of animus toward a disfavored religious minority.” As Judge Harris put it: “The principle that government decision-making should not be informed by religious animus is so well and deeply understood in this country that there are few violations recorded.”

That’s exactly right, and the majority of the 4th Circuit seems to agree, declaring that the ban is “not only a likely Establishment Clause violation, but also strikes at the basic notion that the government may not act based on ‘religious animosity.’”

Today’s ruling is so important because it is imperative that the Supreme Court understands how far the Muslim ban falls short of our fundamental constitutional commitments. The Supreme Court justices, like the rest of us, have been living in a country in which a Muslim ban has been official government policy for over a year. It’s only natural that the outrage that this idea originally provoked may dull somewhat in the face of a constant rush of newer shocks and provocations from the Trump–Pence administration. But we – and  the Supreme Court – must  not lose sight of how truly outrageous and antithetical to the basic promises of the Constitution a “Muslim ban” is.

To quote today’s ruling again, “on a fundamental level, the Proclamation second-guesses our nation’s dedication to religious freedom and tolerance. . . . When we compromise our values as to some, we shake the foundation as to all.”

That’s why Americans United will not stop fighting this ban. When it comes time for the Supreme Court to hear this issue, you can be sure that we will be there to say that, in America, there can be no Muslim ban, ever.