When he was out on the campaign trail last year, candidate Donald Trump promised to appoint conservative U.S. Supreme Court justices who'd adhere to a strict reading of the U.S. Constitution and return law-and-order to the land.
Earlier this year, President Trump got one of those justices in U.S. Appeals Court Judge Neil Gorsuch, restoring a theoretical 5-4 conservative majority to the high court.
But as the Supremes get ready to hear a challenge to the administration's travel ban (and we can call it that, because Trump is calling it that), getting the affable Gorsuch onto the bench may not be enough to ensure that the ban survives.
That's because the high court's wildcard, Justice Anthony Kennedy, could end up having the final say over whether the ban lives or dies.
At the heart of the challenge to the administration's ban on travel from six, Muslim-majority countries is whether it's motivated, as the administration says, by national security interests, or if it's an exercise in anti-Muslim animus.
In an extraordinary ruling last month, the Fourth Circuit U.S. Court of Appeals issued a stinging rebuke to the administration, effectively accusing it of lying about its motivations.
"Trump's own statements show that he lied when he said the purpose of the executive order was national security," Bloomberg View columnist Noah Feldman, a Harvard Law professor, wrote in a May 25 column.
"Once that conclusion was on the table," Feldman observed, Chief Judge Roger Gregory, a Clinton appointee, "easily went on to show that such animus violated the establishment clause by sending a message to Muslims that they are outsiders in the political community."
Most observers agree -- including the husband of White House counselor Kellyanne Conway -- that Trump did himself few legal favors with a Monday tweet storm related to the ban.
And that's where Kennedy, a Ronald Reagan appointee, who essentially wrote the book on animus, enters into things.
In a must-read on Kennedy, Quartz's Jake Flanagin writes that Kennedy "first identified animus as a contemporary means to invalidate unconstitutional laws in his 1996 opinion in Romer v. Evans," a civil rights case from Colorado that served as a place-setter for the court's 2015 decision legalizing gay marriage.
In Romer, Kennedy sided with the court's majority, which "(struck) down an amendment to the Colorado state constitution which forbade the state legislature and city governments from adopting anti-discrimination laws to protect LGBT Americans," Flanagin wrote.
"The amendment's 'sheer breadth' was "so discontinuous with the reasons offered for it that (it) seems inexplicable by anything but animus toward the class that it affects," he (Kennedy) wrote,'" Flanagin reported.
Flanagin observes -- and I agree -- that it's pretty easy to imagine Kennedy substituting "Muslims" for "gay people" in that analysis and voting against the administration, thus denying it the five-vote majority it needs for the ban to survive.
And if the Romer case was an isolated incident, that might be one thing. In a number of decisions down the years, Kennedy has reapplied the "animus" standard, notably in United States v. Windsor, which struck down the federal Defense of Marriage Act and in Obergefell v. Hodges, which legalized same-sex marriage, Flanagin reported.
In addition, Kennedy's legal reasoning in a 2015 immigration case could also play against the administration.
As Reuters reports, that ruling "involved an Afghan-born naturalized U.S. citizen named Fauzia Din who argued she had the right for a full explanation from the U.S. government as to why her Afghan husband was denied entry. The justices ruled 5-4 against her."
There, "Kennedy wrote in a concurring opinion that in some circumstances the U.S. government's motives in denying someone entry could be subject to legal review," Reuters reported.
If Kennedy decides the administration was motivated by something other than legitimate national security interests, it could be game-over, Feldman observed.
"If Kennedy reads Trump's executive order temporarily blocking immigration from six predominantly Muslim countries as an exercise of anti-Muslim animus, the ban will fall at the court," he wrote.
Kennedy is now 81 years old, and liberal activists have been urging him to stay on through the Trump administration.
As Feldman notes, "I find it almost impossible to believe that Kennedy ... would want to sign an opinion closing his eyes to animus, which he himself did so much to make into a constitutional touchstone," he wrote.
And that could be the administration's worst nightmare.