Second, the opinion emphasized a year ago that, even with the ban in place, there was a requirement for periodic review of the countries subject to it. The majority’s opinion stressed that the presidential proclamation carrying out the ban requires the Department of Homeland Security to assess on a continuing basis whether entry restrictions against particular countries should be altered — and to provide a report to the president every 180 days. Indeed, the majority justices seemed quite taken by the convenient fact that, just 15 days before the case was argued at the Supreme Court, the White House had removed Chad from the list of countries subject to the ban as a result of the 180-day review.

Well, it’s been 14 months since Chad was removed from a ban to which it never should’ve been subject in the first place, and no other country has shared its good fortune. Indeed, not only has no country come off the list since the court upheld the ban, but there’s been no public indication we have found that the required 180-day review is even occurring. If it is, it’s happening entirely in secret — and yielding no alterations. The regular reviews emphasized a year ago by the court’s majority now look even more like something more fictional than a robust evaluation process.

Third, the court’s decision noted that, even while the ban remained in place and even for countries still subject to it, “case-by-case waivers” were available for individuals to allow them to travel to the United States if they could show “undue hardship.” The chief justice’s majority opinion emphasized that the availability of waivers made Mr. Trump’s travel ban more similar to actions of earlier presidents. It also underscored the direction given to consular officers to assess waiver applications while addressing any public safety concerns and broader implications for the national interest.

The waiver program looked like a sham a year ago, as a consular officer made clear in a sworn affidavit in another matter and as Justice Stephen Breyer emphasized in his powerful dissent. It looks like even more of a sham now. According to the Trump administration’s own data, between December 2017 and May 2018 approximately 98 percent of those who applied for a visa to travel to the United States did not receive a waiver. More recent reporting still shows only 6 percent of those subject to the travel ban receiving waivers. What’s more, the process even for seeking a waiver has remained opaque to the point of being inscrutable. So have the criteria by which consular officers evaluate the waiver applications they do receive. The waiver process held up by the court’s majority a year ago continues to let down applicants today.

Reasonable people can differ about whether these three points were obvious to the court a year ago, and the court’s defenders are right to suggest that it doesn’t usually second-guess presidential determinations or try to foresee the future. But the point isn’t just that the court’s decision a year ago has aged poorly — it’s that key foundations for that decision have crumbled. The court’s majority embraced Mr. Trump’s representations that his travel ban was temporary, subject to regular reassessment and softened by the availability of waivers. Those premises looked arguably faulty then but are now downright far-fetched.