National Review editor Rich Lowry has an entertaining column about the rise of Donald Trump whose core thesis is that Trump's rise highlights the unexpected weakness of the GOP's supposedly "strong field" of mainstream contenders. It's an interesting idea (see Daniel Drezner for more on this theme), but it's wrong.

Though Trump is anything but a banal person, his rise in the polls has a very banal explanation — he stands for some ideas that are reasonably popular, but that no other well-financed candidate has previously articulated. Donors don't like these ideas, so candidates normally don't express them. But this bloc of opinion has existed for a long time and represents a huge swath of the Republican Party rank and file. Trump is the egomaniacal opportunist who's finally giving voice to those ideas. And much of the American establishment is in deep denial about their real appeal.

Lots of people agree with Donald Trump

As Lee Drutman has written, the Trump combination of far-right views on immigration plus center or left views on Social Security is pretty popular. More than one-fifth of the electorate endorses the Trump view that "immigration should be decreased a lot" while Social Security should not be cut. All mainstream Republican Party figures, by contrast, hold views in the right-hand column of Drutman's chart — opinions that collectively secure the endorsement of less than 10 percent of the electorate.

With Trump holding a popular opinion while about a dozen other Republicans all crowd into an incredibly unpopular niche, the striking thing is that Trump is punching well below his potential weight. Perhaps all the apparently clownish, seemingly off-putting stuff that he does is, in fact, counterproductive and he would do even better if he combined his ideas with a more mainstream presentation.

But these generally unpopular views are popular with the kind of people who finance the Republican Party. There are a lot of rich people out there who want to see their taxes cut, and most of them understand that in the long term only paring back America's big retirement programs will make those tax cuts possible. Those donors often favor relatively high levels of immigration and are a little put off by excessively hardcore social conservatives, but they demand orthodoxy on economic policy — even when it makes it harder to win elections.

Trump-like movements are popular globally

The Trump phenomenon is, in a way, uniquely American. But to people who follow European politics it's also very familiar.

The big political trend over the past 15 years has been the rise of a series of new populist-rightist parties — UKIP, the Danish People's Party, the Sweden Democrats, the National Front, the True Finns — who emphasize nationalist themes and hostility to immigration while offering a mixed bag on the welfare state.

That a similar movement would gather steam in the United States is not so surprising. The main difference is that the open nature of US political parties and the unforgiving nature of the election system makes it more reasonable for Trump to run in a Republican primary than to start his own political party.

Rick Santorum and Mike Huckabee did well

In retrospect, Trump 2016 was prefigured by the surprisingly resilient presidential campaigns that Mike Huckabee and Rick Santorum ran in 2008 and 2012.

Both Huckabee and Santorum fit into a broadly similar ideological niche to Trump's, one that deemphasized the GOP donor base's tax-cutting and entitlement-slashing priorities in favor of the cultural politics of older, white, working-class Americans. Compared with Trump, both Huckabee and Santorum had a big advantage — they were real Republican Party politicians with practical campaign and governance experience.

But they also had a huge disadvantage — their ideas were anathema to the party's donor base, and they were not, personally, billionaires. Trump, conveniently, is a billionaire, so his lack of fundraising ability isn't a big problem.

The establishment is in denial

The fundamentals are clearly there for a right-populist candidate to secure mass appeal and really move the needle in American politics. What continues to be missing is the appropriate candidate: someone who has both the right résumé (like Huckabee in 2008) and the necessary financing (like Trump in 2016) to be a plausible presidential nominee. And this isn't a coincidence — the Trump ideological niche is not one that appeals to very many rich people.

This @RichLowry piece is essential to getting Trump: He's filling a vacuum left by an unexpectedly impotent field http://t.co/IMeOkZTWj2 — Alex Burns (@alexburnsNYT) August 27, 2015

Still, Lowry's column and its embrace by many in the media show an American establishment that continues to be in denial. Trump is a bit of a freak show, so there is an impulse to say that he is succeeding because he is a freak show, a one-off who provides an amazing story during the doldrums of summer with no wider significance for American politics.

The truth is the opposite. Trump is succeeding because he is articulating views that are widely held among American voters but normally suppressed in the political system due to the power of the donor class. The voting bloc that he's tapping into has been tapped previously, and will be tapped again in the future — possibly in more effective ways by more conventional politicians.

VIDEO: Donald Trump on campaign finances