This post is part of Polyarchy , an independent blog produced by the political reform program at New America , a Washington think tank devoted to developing new ideas and new voices.

In the weeks between Donald Trump’s election and his inauguration, commentators and politicians eager to see what kind of president Trump would be mostly looked to his Cabinet choices. And in those Cabinet choices, they saw signs that Trump would govern mostly as a conventional Republican.

Then came his inauguration speech, in which he returned in force to the nationalist-populist themes of his campaign. As with the campaign, his rhetoric went to dark, sometimes apocalyptic places, the places where his mix of strong-armed economic nationalism and tough law and order would be most needed.

So the question remains: Will Trump try to remake the Republican Party in his nationalist-populist vision? Or will he just govern as a conventional conservative Republican?

I’ve long viewed Trump as a potentially realigning figure in American politics, shifting the party system toward one in which the Republicans become the traditionalist-nationalist party and the Democrats became the progressive-cosmopolitan party. I still do.

Why so many people still think Trump will be a conventional Republican

I understand why folks on both the left and right would cling to the assumption that Trump will be a normal Republican.

On the right, the instinct to see Trump as a normal Republican mostly springs from wishful thinking. After all, Republicans have waited eight long years to have a president they can call their own. Trump may be a vain and petulant teenager, with some unfortunate impulses. But surely he can be tutored in the ways of the world according to conservative dogma, if only he can be surrounded with good conservatives like Mike Pence and Reince Priebus.

By contrast, to accept Trump as a nationalist populist out of step with conservatism would be to admit defeat prematurely, and to accept that the Republican Party has become something many congressional Republicans have professed to be philosophically uncomfortable with.

On the left, the instinct to see Trump as a generic Republican springs from comfort many have with an existing playbook they used to fight George W. Bush. Liberals think they can hit Republicans on being too pro-business and pro-Wall Street (Look at Trump’s billionaire Cabinet! Drain the swamp? More like fill the swamp!). And they think they can win by defending popular entitlement programs like Medicare and the Affordable Care Act and Social Security. After all: Remember what happened when Bush tried and failed to privatize Social Security? Surely, these working-class Trump voters will come back to the Democratic Party when they see what Republicans really want to do to their benefits. Right? Right?

By contrast, to accept Trump as an economic populist might be to (gasp!) actually agree with him on some issues. Many Democrats have long expressed concern over trade deals. Democrats loved massive infrastructure building when Obama called for it. What if Trump wants to expand Social Security and Medicare? Will Democrats now have to adjust their worldview to stay opposed to Trump? Nobody wants to have to contemplate that level of cognitive dissonance. Yet if Trump has been consistent about anything throughout his political career, it’s been his populist economic nationalism. Go back 30 years, and his core message is remarkably consistent.

Social issues are different. Almost certainly, Trump will be a conventional Republican on social issues. He’s shown much more flexibility on these issues, to placate Republican orthodoxy. And if anything, he’ll be further to the right on race and immigration and criminal justice issues, which will certainly provoke plenty of liberal backlash.

Why Trump’s Cabinet picks are not a reliable guide to his administration

Those who want to over-interpret from his Cabinet picks should keep two things in mind.

First, we should remember that Trump didn’t give much thought ahead of time to a Cabinet. So to the extent that his Cabinet reflects anything, it reflects a chaotic scramble to find plausible individuals who were able to hit it off personally with Trump, not some deep-seated and carefully planned-out vision. Unlike Hillary Clinton, Trump did not have a clear plan of action upon election.

Second, because Trump’s Cabinet was not well-planned and most of his appointees are relatively new acquaintances, Trump is unlikely to have any deep trust in anybody he has appointed. Sure, he says he will give his Cabinet plenty of autonomy. But he will also be watching them closely, with loyalists assigned to monitor all secretaries. Presumably, Trump sees his role as the visionary, concerned only with “greatness.” He’s the man who steps in at the end of the episode to evaluate who’s done “great.” If he’s not satisfied, remember his catchphrase: “You’re fired!”

Trump has no idea what he’s going to actually do — only vague instincts

Running a country is not like running a business. Politics involves a series of hard trade-offs, with no easy answers. If Trump thinks he can devise great new solutions to persistent public policy problems that have heretofore not been discovered by Washington wonks, he will be disappointed.

Take Obamacare repeal. Trump presumably has no well-formulated ideas. But to the extent he has instincts, they are decidedly populist: some kind of “insurance for everybody” that involves taking on the big drug companies. It’s hard to square these instincts with plans congressional Republicans have been developing. And while Obamacare has its problems, there is a cost-versus-coverage trade-off that nobody has yet resolved, despite many, many smart people giving it a try. It seems unlikely Trump will find a way to get more coverage at less cost — though he may certainly find a way to disingenuously market worse coverage at higher costs, or to essentially repackage Obamacare as Trumpcare.

The same problem of details applies to his economic nationalism. It’s out of step with Republican orthodoxy and impossible to deliver on. Pulling out of the Trans-Pacific Partnership was easy. The deal had not been signed. Renegotiating NAFTA will be hard. Enacting a border tax will be hard. A corporate tax overhaul will be hard. Getting rid of 75 percent of regulations will be almost impossible. And bringing back manufacturing jobs, in an age of automation and robotics, is impossible.

Similarly, his cowboy “America first” foreign policy and Russophilia are also at odds with most congressional Republicans, who are still mostly in favor of maintaining NATO and the post–World War II global order and view Russia as an enemy. Trump promises to destroy ISIS. And how, exactly? As with everything else, he promises there are no clear plans, and the promise is nearly impossible.

All of this gets at the same underlying problem: Trump has zero experience in the ways of Washington, and appears to have no well-worked-out policies. Yet he has pretensions to grandiosity that far outstrip the art of the possible. And he is clearly bruising for a fight against anyone who stands in the way of that grandiosity, whatever it is.

How to actually fight Trump

Democrats who want to fight Trump on economic issues may find him a squirrelly target, happy to distance himself from his party’s orthodoxy, especially on trade and entitlements. They may find themselves doing more shadowboxing than they expect.

Here, it’s worth remembering that it’s unlikely Trump has forgiven Paul Ryan and other establishment Republicans who tried to distance themselves from him during the campaign. Trump can’t help but want to show Ryan and others who’s boss. Economic populism (and possibly immigration) is the issue on which he can best accomplish this. Already, Ryan is backtracking on his support for free trade. Trump would surely love to beat him up some more.

Democrats who want to fight Trump on social issues, by contrast, will find a more reliably conservative adversary. But they also need to be careful here. To win back the House and the Senate, Democrats need to expand somewhat beyond their cosmopolitan urban strongholds. Getting caught up entirely on social issues may make it hard for them to accomplish this. Moreover, to the extent that Trump fails to deliver on his economic and foreign policy promises, he can turn to divisive issues around culture and identity to keep his core voters distracted. The more Democrats focus on these issues to the exclusivity of other issues, the easier it will be for Trump to pick these fights to his benefit.

Democrats’ best chance of challenging Trump will depend on some mix of corruption, constitutional norms, civil liberties, and foreign policy — issues where Trump is almost certainly likely to go too far and/or get in over his head, and where Democrats and Republicans could learn to work together.

Trump’s one consistent ambition has been to shake up the established way of doing business in Washington. But what fights will he actually pick? And how will he pick them? Hard to be sure. I’d still bet on him pushing hard on the economic populism angle, given how core it’s been to him for his entire political career. I’d also bet that any plan that depends on him being a conventional Republican, especially on economic policy, is almost certain to need updating when it meets the battlefield.