For as long as Donald Trump has been leading in polls of Republican presidential primary voters, there has been a rising wave of discontent among a large subset of conservatives. With the Sarah Palin endorsement, the dam finally burst and Trump is unlikely be able to persuade Mexico to pay for its repair.

These are not just casual, rank-and-file conservative voters either. Some of those dismayed at Trump's success have dedicated their lives to spreading conservatism as they understand it. One representative piece by attorney and conservative writer Sarah Rumpf was titled "Sarah Palin just threw away years of goodwill as a principled conservative."

Today, Palin is standing in Ames, Iowa, to put her support behind someone who cannot be trusted to protect the unborn, who has twice traded in his wives for younger models (literally), who claims to be for the "little guy" but who has been all-too-willing to use government as a hired thug to line his own pocket, and who spent years making significant donations to Hillary Clinton, the likely Democratic nominee. [IJ Review]

"Maybe the Tea Party isn't splintered and weak," wrote National Review's Jim Geraghty. "Maybe it's dead." His colleague Charles C.W. Cooke wondered if the Tea Party had instead descended from movement to racket. "Today was the day that Rick Santelli's famous yelp finally melted into populism and avarice," he argued. "Today, at about 10 minutes past six, P. T. Barnum beat out Hayek for the soul of the insurgent right. Today, the rebels became the charlatans they had set out to depose."

On social media sites and conservative listservs, it was easy to find people despairing of conservative Republicanism. They claimed to not recognize Palin, the Tea Party, or even conservatism itself anymore. And these were just the self-described conservatives, not to mention their libertarian allies.

But the Tea Party was always paradoxically a mixture of libertarianism and red-state identity politics. The former was as much a rebuke to George W. Bush as Barack Obama and the latter's adherents would have been at home with a Republican president who made Bush look like Ron Paul. It was always partly about fighting the left and partly about fighting bipartisan big government. It was always one part Hayek's Road to Serfdom, another part your uncle's chain emails about Obama's long-form birth certificate.

Palin has often straddled this line, so much so that she gave a shout-out to Rand Paul in the middle of her Trump endorsement, but her appeal has always been as much about who she is and what she represents as much as what she believes. She was the Bible-studying, gun-toting, hockey mom who affirmed social conservatism while defying stereotypes about what a social conservative — normally depicted as prudish men seeking to control women's bodies rather than independent women — looked like.

As such, Palin was always more of a populist than a small-government gal, even as she tried, along with the broader conservative movement, to harmonize these two Tea Party tendencies. Once she resigned the Alaska governorship, she just became a bigger part of the conservative celebrity culture. Her Trump endorsement really isn't a major departure for her or the political movement she represents, even if it is something many members of that movement find distasteful.

Even before the Tea Party, modern American conservatism has largely been about convincing people with normally patriotic instincts and traditional values that their political champions are advocates of (relatively) limited government. That's why millions of people who voted for tax-cutting, deregulating Ronald Reagan had previously voted for wage-and-price-freezing Richard Nixon and even segregating, states' rights statist George Wallace before that.

Much of this isn't even unique to conservatism. For most people politics is about personality, identity, and group loyalties. This is more like rooting for a sports team than support for particular ideas, ideology, or policy. It's always has been this way and probably always will be. Even plenty of deeply ideological people who marched in the streets during Bush's Iraq war made nary a peep when Obama bombed Libya; lots of people on the other side would have soured on Iraq much sooner if the war had been ordered by President Hillary Clinton instead.

This problem is particularly acute for conservative elites, however. There's been a disconnect between the movement and the base on presidential candidates for years. Jack Kemp was more popular with the former than the latter. Before Trump outlasted Scott Walker, Pat Buchanan trounced Phil Gramm.

A lot of American fiscal conservatism isn't libertarianism per se but actually social conservatism, a form of the Protestant work ethic. Conservatives have struggled to persuade even their own voters to fight for limited government when programs aren't being pushed by liberal Democrats they distrust and benefit people who work. If a nontrivial percentage of culturally conservative white voters no longer sees a meaningful connection between limited government and their values, interests, or even livelihoods, that's going to be a problem for the right that outlasts Trump.

Many of the people today voting for Trump not so long ago were voting for Ted Cruz, Marco Rubio, Rand Paul, and even Carly Fiorina in down-ballot races. What changed that made them no longer see such votes as being in their interests? In the coming Republican primary battle between frustrated movement conservatism and Trump's more idiosyncratic right-wing politics, that is the $19 trillion question.