The most striking thing about Donald Trump's presidential campaign is how mindless it is. There is no plan behind it, no grand strategy or driving ideological goal, no political mission statement to speak of. The campaign seems to consist almost entirely of Trump—now leading the GOP field by a solid 10 point margin—roaming from microphone to microphone saying whatever ridiculous thing comes to his mind at the moment. He is calculating only in the sense that he gravitates toward attention-grabbing overstatement. Trump, who is fond of calling enemies morons, dummies, and lightweights, is running the stupidest presidential campaign in memory.

The empty bravado of Trump's presidential campaign is captured nicely in this revealing quasi-profile from National Journal's Andy Kroll. I call it a quasi-profile because mostly what it reveals is how little there is to learn about Donald Trump, presidential candidate.

Like any decent journalist, Kroll initially resisted the Trump phenomena, believing it to be a sideshow. But as Trump gained popularity in the GOP primary polls, Kroll set out with a somewhat novel plan to investigate the candidate: Rather than focus on the circus, he would make an earnest attempt to determine what Trump actually wanted to do as president.

Kroll flew to Laredo, Texas to watch a few of Trump's media events near the border, and he contacted Trump's not-particularly-responsive campaign team in a fruitless attempt to obtain responses to a few fairly basic questions ("Aside from immigration, if you were to put your name on one piece of domestic-policy legislation, what would it be?").

Ultimately Kroll came up empty. Not because he didn't put in the effort, but because there's simply nothing to find.

Kroll's conclusion: "I have zero to report about Trump's plans for actually being president—except that, from all available evidence, he hasn't given it a moment's thought." Outside of immigration, Trump is uniqely agendaless, lacking even dumb policy gimmicks (even Herman Cain had 9-9-9). His campaign is an end unto itself.

What this means is that you cannot talk about the substance of Trump's campaign, because, aside from a kind of generalized angry nativism, there isn't any. Trump's past record of support for liberal policies (gun restrictions, government-run health care, special taxes for the very wealthy) only tell us how little his support for any particular position matters. Even if there was any policy substance to be found, it would be beside the point.

So why is it that so many Republicans seem to like Donald Trump? Why does his mindless, brazenly uninformed approach to campaigning resonate so much with so many? What, if not his policy ideas and plans for the presidency, explains his appeal?

For many, it seems, it's more about style, and a sense that Trump stands outside the political status quo—that he is more like a everyday person than a scripted political actor. (Trump himself has talked up his refusal to rely on pollsters and political consultants.)

Talking to The Wall Street Journal's Peggy Noonan last week, one Trump admirer—a anonymous 60ish woman from Georgia—put it like this:

"The whole country will be in better shape. And ISIS won't like it that he's in charge. He's very wealthy and can turn around the economy. He'll get things moving. The Donald will kick a—." She knows other supporters locally and among friends of her son, an Iraq vet. "They're completely disgusted and just furious, and he's igniting their passion. He's telling them 'I will make this country great again,' and they believe him." Mr. Trump is dismissed as exciting, but "we have to get excited to get up out of the chair to vote."

It's easy to make too much out of an interview with a single individual, and no doubt others would characterize their interest in Trump differently. But this tracks closely with the explanations from other admirers as well as my own interactions with Trump supporters. And what it suggests is that the Trump crowd has thoroughly tired of conventional politics and conventional politicians. The draw of Trump's candidacy is that he is so very obviously not bound by these conventions—that he is not a conventional politician, nor even really a politician at all. He doesn't have policy ideas or governing plans to speak of? So what? Those are for politicians. Trump's politics are a kind of anti-politics, and his lack of a traditional political agenda only adds to his anti-political appeal.

The rise of anti-politics, at least on the right, can be traced at least in part to a distrust in Republican elites, suggests The Weekly Standard's Jay Cost:

Since 2010, the actions of congressional Republicans have mostly fallen shy of campaign promises. From a short-term perspective, this may have been necessary. It is hard to mobilize your voters by saying, "Vote for me to stop the president from doing worse." It is better to say, "Vote for me to roll back the president's actions." But over time this rhetorical overreach has facilitated a climate of distrust. Republican voters increasingly believe that their leaders, even if they had complete control of government, would not do half of what they promise on the campaign trail.

Trump's campaign solves this problem by effectively promising to do nothing in particular, which I suppose is about what one could expect from a Trump presidency, to the extent that one can even imagine such a thing.

I suspect, though, that most of Trump's supporters, rather like Trump himself, have put very little effort into imagining a Trump presidency, except to idly fantasize about all the ways that it would be different and awesome and better. He would be an exciting, deal-making, ass-kicker who would strike fear into the hearts of America's enemies, and he would do this simply by virtue of being Donald Trump, in all his glorious, exciting Trumpiness.

What Trump offers is a fantasy of governance without negotiation, of economic success without policy detail, of a president who does not particularly feel the need to act presidential. It's a fantasy of politics without politics, for people who just don't want to think about it too much. In this view, the fact that Trump has clearly put so little thought into it himself makes him seem sensible and relatable. All of which is to say that the mindlessness and stupidity of Trump's presidential campaign are not incidental to the candidate's recent success. On the contrary, they are key to his appeal.

All of this is, in some sense, an outgrowth of the Republican party's own mindlessless during the Obama era. The party has consistently refused to be clear about its domestic policy goals, and what it plausibly expects from government. And while it has not, as a general rule, fully embraced Trump levels of of vapidity, it has embraced figures like Trump, and allowed them to rise within the party.

This was clearly evident, albeit in a much milder form, in Mitt Romney's 2012 run as the GOP nominee, which was marked by its consistent lack of policy detail, and by Romney's unwillingness to provide clarity about his policy plans. Romney did, however, praise Trump's "extraordinary ability to understand how our economy works and to create jobs" as he accepted Trump's endorsement.

It's evident still, in the party's ongoing inability to unify around an Obamacare replacement, to reckon with the realities of immigration, to discuss in detail what cutting the federal budget would really entail. It is telling, I think, that a top priority for one of the major intellectual movements on the right is simply to encourage Republicans to engage with policy ideas, at all.

Trump's candidacy is what a refusal to engage with policy and its practical realities looks like when taken to an extreme. He is a mindless candidate for a party that for years has casually courted mindlessness, and is now faced with the worrying possibility that it might prevail.