There is a powerful, nuanced line of argument under development in progressive legal and economic circles, which holds that antitrust laws need to be modified and deployed against tech platform monopolies—and that Amazon in particular is among the worst offenders.

This view doesn’t unite all Democrats, and California Democrats are particularly resistant to it, but the concerns antitrust reformers have raised about tech giants (like their broader concerns about airline and cable oligopolies and economic concentration in general) can’t easily be brushed aside.

Part of what makes the case for reform persuasive is that it reflects a general economic and political theory that has nothing per se to do with Amazon, and would apply equally to all corporate entities.

Those who are persuaded by the case against Amazon may thus be tempted into a temporary meeting of the minds with President Donald Trump, who is engaged in a months-long, one-sided political assault on the tech giant. Trump, unlike antitrust reformers, is motivated not by any neutral principle, but by the fact that Amazon’s founder, Jeff Bezos, also owns the Washington Post, which Trump finds insufficiently deferential and wants to destroy as a mediating institution.

And yet, because their interests happen to align with respect to the ideal disposition of Amazon, some liberals believe an alliance of convenience is in order.

“[I]t’s entirely possible that this is what’s motivating Trump,” writes Damon Linker. “But does that mean it makes sense for liberals to rally around Bezos in response? Not at all—at least not if the left in this country wants to stand for more than reflexive opposition to whatever Trump says and does.”

I set up the conundrum this way to underscore the fact that the logic actually runs in the opposite direction. The only reason to align with Trump against Amazon is to signal, at enormous cost, that the opposition to Trump is not reflexive. There is no principled case for liberals—even Amazon skeptics—to align with Trump on the Amazon question, just as there was no principled case for liberals to support Trump’s interest in thwarting the AT&T/Time Warner merger, which stemmed entirely from his desire to punish CNN for not being more Fox News-like. The proposition at hand is not “what should the American government’s antitrust policy be?” It’s “do we want to enable the Trump administration to selectively enforce antitrust law for corrupt ends?”

The answer to this question should be obvious. It is one of the places where the broad Trump resistance’s reflexive defense of “norms and institutions” is most firmly grounded. And the same instinct or reasoning that drives liberals to defend a corporate behemoth like Amazon applies more generally to institutions that, under other circumstances, liberals would be harder-pressed to defend.

TPM’s Josh Marshall underscored the point nicely when he connected the case against Trump’s pretextual anti-Amazon arguments to the case for supporting Andrew McCabe, the fired deputy FBI director, in his expected litigation against the Trump administration. It is a case that has nothing to do with being reflexively anti-Trump, or reflexively pro-FBI or reflexively pro-Amazon. It is a case against making ends-justify-the-means alliances with Trump in instances when Trump’s motives are corrupt, and for opposing the corruption vocally in some way.

It would be possible in theory for liberals to appropriate Trump’s attacks on the FBI and Justice Department to advance the progressive goal of drawing attention to law enforcement abuses, rather than “side” with the cops and prosecutors against Trump. But liberals aren’t confronted with a choice between valorizing the FBI and using Trump to help draw critical scrutiny toward the FBI. It’s a choice between running progressive criticisms of law enforcement agencies on their own track, and helping Trump turn the FBI and DOJ into tools of his personal and partisan control.

Liberals rightly understand that they should defend outlets like CNN and NBC (corporate behemoths in their own rights, both of which have served Trump’s interest in different ways) when Trump attacks them to advance the objectives of Sinclair Broadcast Group.

Trump is not simply trying to destroy non-partisan journalism as a vocation (though that is a longstanding goal of his and of the broader American right). He is signaling to CNN and NBC and Jeff Bezos and telecommunications companies that if they have business before the government, they might want to get into the business of advancing pro-Trump propaganda. It would be foolish to treat Trump’s entry into the controversy over Sinclair as if he were simply a consistent and principled media critic, but by the same token it is wrongheaded to treat his entry into the antitrust debate as if he intends to take on all monopolies irrespective of their loyalty to him, or his attack on the FBI as if he cares about the FBI’s abuses of power writ large. None of it is offered in good faith.

This is not to say every step every liberal has taken in opposition to Trump has been effective or wise. Andrew McCabe probably didn’t need $500,000 in donations for his legal defense fund, and even though Trump is trying to ruin the lives of federal officials who pose legal danger to him, there are probably better ways to symbolically rebuke Trump than sending McCabe money he doesn’t need. More broadly, Trump’s victory has given rise to an unhealthy but understandable tendency among a subset liberals to take refuge in the hope that lonely hero figures will save us from him—even if the heroes are prosecutors, spies, or tech billionaires, who deserve great scrutiny in their own rights.

It is not contradictory, though, to believe that while Amazon should be broken up as part of a broader programmatic rethinking of American antitrust law, it should not be broken up as part of Trump’s efforts to punish his perceived enemies and create a patronage economy. To the contrary, establishing a new antitrust regime that enjoys public legitimacy, or reforming the criminal justice system in a productive way, requires liberals to stand against Trump’s efforts to corrupt and destroy public faith in both.