Let’s start with the law.

The president of the United States has power to bar “any class of aliens” both as immigrants and as nonimmigrants and to impose on their ordinary comings and goings “any restrictions he may deem appropriate.”

That’s the language of the U.S. Code, the law of the land as enacted by Congress, under Congress’ own constitutional power over immigration and naturalization.

Presidential power is never absolute, of course. It’s always subject to the Constitution. Many have argued that Trump's ban is unconstitutional because—as the president himself has repeatedly said—it’s intended to ban Muslims, and should be regarded as prohibited religious discrimination.

But here’s the problem for those making the argument: It’s firmly established U.S. law that the rights of the Constitution belong only to Americans. The U.S. Army can strip enemy combatants of weapons without offending the Second Amendment right to carry firearms. It can billet troops in private dwellings overseas without offending the Third Amendment. The NSA can intercept foreign communications without regard to the Fourth Amendment. The U.S. courts do not hear cases from foreign nationals who complain their due process rights under the Fifth Amendment have somehow been infringed. And so through the gamut.

Where do foreign nationals then acquire their supposed First Amendment right to enter the United States without religious discrimination?

The answer offered by Judge Derrick Watson’s opinion is a judicial reach of a kind that might sound clever to the student editors of an academic law review—but that should worry all Americans in real life. By barring foreign Muslims, the opinion argues, the Trump administration has signaled disfavor of domestic Muslims as well, thereby violating their First Amendment rights to religious equality.

Not only that! Watson’s opinion further contends that this argument is so convincing that it is “highly likely” to prevail on the ultimate merits—and for that reason, that he is justified in issuing immediately a temporary restraining order against Trump’s ban.

This double argument is bold, to put it mildly.

What it does, in effect, is globalize the First Amendment (and possibly other amendments too) provided only that a fellow adherent of that religion live inside the United States.

This approach is so ambitious and so new that it renders it incredible Judge Derrick Watson’s claimed certitude that the plaintiffs are “highly likely” to prevail. Their chances are at best touch-and-go; at worst, probably doomed.

Frankly, under any other president than Donald Trump, it seems impossible that a federal judge would have expressed such certitude—or granted their requested order. The federal courts have historically granted large deference to presidential power over immigration and naturalization. The Supreme Court ruled as recently as 2015 that the president could deny a visa to an alien for no reason at all! In answer to an alien who contended that the U.S. government had violated her due process rights, the court ruled:

She claims that the Government denied her due process of law when, without adequate explanation of the reason for the visa denial, it deprived her of her constitutional right to live in the United States with her spouse. There is no such constitutional right.

Why then did Watson accept the far-fetched argument that aliens can acquire First Amendment rights at second-hand? Watson candidly confessed that he was swayed by the avowals by the president and his senior aides that their motives were indeed based on irrational religious discrimination. “In this highly unique case,” he wrote, “the record provides strong indications that the national security purpose is not the primary purpose for the travel ban.” He could not overlook "significant and unrebutted evidence of religious animus driving the promulgation of the Executive Order and its related predecessor.”

To amend an old saying: Bad presidents make bad law. Because President Trump is behaving in an unprecedented way, Watson feels called upon also to behave in an unprecedented way. In order to defend a constitutional value—equal treatment of all American religions—Watson has issued an order that corrodes the constitutional system itself. It’s a lose-lose proposition, because either way a constitutional norm would be weakened before the world.

Watson’s imaginative reasoning in Hawaii v. Trump asserts a new judicial power to disregard formal law if the president’s personal words create a basis for mistrusting his motives. In the age of Trump, many will be sympathetic to this judicial power—but it is crammed with dangers, too. Not the least of those dangers is that this new rule creates incentives for the president to race to cram the courts with his people in the possibly brief window in which his party controls the Senate. If presidential power ebbs and flows according to the opinions the judges of the moment happen to feel about the character of the president of the moment, the day has come when the courts too must become a prize of hyper-partisan politics.

I’ve argued before in this space that Donald Trump is a uniquely dangerous president. Watson has now revealed to us another of those dangers. In response to the danger posed by Trump, other American power holders will be tempted to jettison their historic role too, and use any tool at hand—no matter how doubtfully legitimate—to stop him. Those alternative power holders may even ultimately win. But in winning, they may discover themselves in the same tragic position as that Vietnam-era army officer who supposedly said: “We had to destroy the village in order to save it.”