Is billionaire and Republican frontrunner Donald J. Trump a conservative, or not?

Fox News’ Jesse Watters has made the best possible case that he is.

“Come on, let’s talk about his conservative principles on the three core issues Donald Trump is about; immigration, national security and jobs. He is the most conservative guy out there and he is setting the agenda,” Watters said on Friday, responding to National Review‘s anti-Trump manifesto. He could have added a few others, like guns.

But that’s not quite convincing enough for many conservatives. Trump’s vehemence about his views should not, and does not, obscure the fact that they are, for the most part, very new.

This is a man, after all, who criticized 2012 Republican presidential nominee Mitt Romney for using the term “self-deportation” because it was “mean-spirited.” That was, for those keeping track, one election ago.

Now Trump wants all Muslims barred. (Ahem.)

True, Trump has been willing to sacrifice his own brand for the sake of his newly conservative posture–a sign that he is serious.

But let us stipulate, for argument’s sake, that Trump has a “mixed record on conservatism,” as my colleague Ben Shapiro put it rather diplomatically.

There are many conservatives who still support him wholeheartedly, and there is a real conservative case for Trump. And I say this as an observer who has been skeptical of Trump from the start.

The Buckley rule. William F. Buckley, Jr., whom Trump cites to defend “New York values,” urged conservatives to support the most conservative candidate who can win. And Trump may be the only one, in an election that will decide the Supreme Court’s future.

Whatever the head-to-head polls say on any given day, unless she is indicted, Hillary Clinton is likely to win this year. She has the Electoral College in her favor, and the media on her side.

Only Trump has shown the daring necessary to challenge Clinton’s built-in advantages.

Sen. Marco Rubio (R-FL), who in theory is the most “electable” Republican in the field, for example, declined to target Clinton over her role in her husband’s scandals. Trump, in contrast, released an ad featuring not only Monica Lewinsky, but also Anthony Weiner. He claims credit for Hillary’s slump in the polls against Sen. Bernie Sanders (I-VT), and he is partly right.

Other candidates–Wisconsin Gov. Scott Walker, for one–looked amazing on paper but failed to connect with voters in practice. Cruz, Trump’s closest rival, may yet win Iowa, and has the ability to contest every primary, but has renewed doubts about his ability to win a general election after his “New York values” attack.

Trump, meanwhile, has re-discovered the “Reagan Democrats,” the Holy Grail of Republican politics. He may be the only hope.

The consequentialist case. Trump’s value to conservatism is not what he believes, but what his election would do, regardless of his own policies.

For one thing, as I have argued before, the fact that there is such strong conservative opposition to Trump, as well as a fervent desire among establishment Republicans to be seen opposing him (even if they do say they prefer him to Cruz), means that if he won, Congress might finally stand up to the executive branch.

That is why the possible excesses of a Trump presidency are less fearsome than many think. Much of what he says he wants to do may be unwise (e.g. 45% tariffs on China), or unconstitutional (e.g. broad surveillance of mosques). But Trump will enjoy less deference from a Republican Congress than Obama has, and will have no help at all from the mainstream media. That should please constitutional conservatives who want to restore the balance of powers.

Moreover, just by winning the nomination, Trump will have advanced the conservative cause. While he may have held left-wing views in the past, Trump has largely been running to the right, at least in the primary, affirming the power of the conservative base and conservative principles in an election cycle where the original favorite began by promising to ignore them. A movement that rewards converts even more than stalwarts is well-disposed to expand.

Even if he does not win, a Trump loss would be less damaging to the conservative cause than a loss by any other. If an”establishment” candidate wins the primary, but loses to Clinton, the GOP’s conservative base will give up hope. If a conservative, like Cruz, loses in the general, the establishment will start the purge it has been itching to launch.

But a Trump loss would likely be seen as a once-off, from which both conservatives and the GOP might rebuild.

The importance of victory. But enough about losing. A Trump win would have a galvanizing effect on American politics and the American public, much as Andrew Jackson’s win did in 1828, restoring a sense that voters, and not Washington elites, rule.

Many conservatives–even at the National Review–support him precisely because he is determined to shake up a system in which the status quo is not guided by conservative values but cronyism.

Conservatism is pessimistic about human nature, but optimistic about life. The radical left depends on hopelessness, while conservatism thrives on happiness. Barack Obama’s victory in 2008 was, in a sense, the last achievement of his failed presidency, which still depends on casting America as a nation in crisis.

A Trump win would not, by itself, “make America great again.” but it would urge Americans to believe that we still have the answers within.