NEW YORK -- When the late William F. Buckley Jr. launched National Review six decades ago, he memorably issued a mandate for the conservative magazine to stand “athwart history, yelling Stop.”
The conservative magazine's latest mission appears to be a variation of that: “Stop Trump.”
On Thursday night, National Review unveiled a new issue that makes the conservative case against real estate mogul Donald Trump's bid for the presidency. It features 22 contributors, from veteran magazine writers to popular bloggers to fiery radio hosts.
"We take our heritage seriously," National Review's publisher, Jack Fowler, told The Huffington Post on Friday.
"We were the founding institution of the modern conservative movement and we see ourselves as the protector of what conservative means," he said.
In the new issue, National Review's editors denounce Trump for shifting his political stances and describe him as "a menace to American conservatism who would take the work of generations and trample it underfoot in behalf of a populism as heedless and crude as the Donald himself.”
The Weekly Standard also recently bemoaned Trump's supposed lack of conservative credentials, calling him a "nonconservative longtime Democrat" in an editorial from its Feb. 1 issue.
Conservative media's rupture over Trump is part of a broader dispute on the right about the bombastic ex-reality star’s candidacy. Some leading conservative figures have long criticized him for a lack of ideological consistency -- as well as his harsh attacks on fellow Republican candidates and figures such as Sen. John McCain (R-Ariz.) and his bigoted proposal to ban Muslims from entering the United States.
National Review has played the role of gatekeeper on the right over the years, attempting to drive fringe voices, like the John Birch Society, from what the magazine's editors have deemed to be respectable conservative opinion.
But the media world has radically changed since Buckley denounced the Birchers in the early 1960s, given the emergence of conservative talk radio, Fox News and a plethora of right-leaning blogs, news sites and opinion outlets -- some of which have broadly supported Trump’s candidacy.
Trump also reaches millions and drives political coverage through social media. He immediately issued a broadside against National Review on Twitter.
National Review remains influential, but its clout has arguably diminished over the years as conservative media has become more fragmented. And presumably, many Trump supporters will only dig in their heels after New York and Washington-based opinion magazines -- in other words, "The Establishment" -- align against their candidate.
While National Review's editors clearly don't want Trump to be the Republican nominee, Fowler said the magazine's motivations stretch beyond the current political situation.
"We’re about 2016, but we’re also about 1776," Fowler said. "We’re not abandoning principle and we’re not going to let political leaders claim what conservatism is when they don’t really know what it is."
"If Donald Trump blows through the primary, does that mean we’re irrelevant? Does that mean we failed?" he asked. "In some sense, that means we failed. But we’re about the truth, and the truth wins in the long term."
What National Review is doing now, Fowler said, "may be felt 10 years from now or 20 years from now."
However, the magazine is paying a price in the short term for its anti-Trump issue, with the Republican National Committee disinviting it from a CNN debate next month. (Originally, National Review was partnering with NBC for the event, but after CNBC's much-criticized October debate, the party instead awarded the debate to CNN earlier this week.)
The RNC specifically brought in conservative outlets this election cycle because of its perception of a liberal bias in the media. So, networks sponsoring GOP debates -- with the exception of Fox News and CNBC -- teamed up with right-leaning magazines, news sites, and radio networks.
Fowler said National Review had been in talks with CNN earlier this week to prepare for the debate and address issues surrounding it -- including whether Rich Lowry, who is National Review's editor but also a Fox News analyst, could contractually take part in a CNN event.
But Fowler was informed last night that no one from National Review could participate in the debate because the magazine was being removed from the event. RNC communications director Sean Spicer confirmed to HuffPost that the magazine was disinvited, but did not provide additional comment. Explaining the decision, Spicer told BuzzFeed that "a debate moderator can't have a predisposition."
Earlier this month, the New Hampshire Union Leader -- which endorsed New Jersey Gov. Chris Christie (R) and has harshly criticized Trump -- was removed from an ABC News debate.
"The reason National Review and Salem Radio and these other entities have been brought to the table is the belief that the traditional media is biased," Fowler said. "We’re brought in to counterbalance. National Review is now not good enough, but George Stephanopoulos is?"
(Stephanopoulos actually lost his chance to moderate a debate after word got out that he'd donated to the Clinton Global Initiative, but other mainstream media figures are permitted to moderate.)
"It’s their party; they do with it what they want," Fowler said. "We don’t own it. I think they were very hasty and very presumptive in the action they took. I don’t think it will be to their benefit."
Fowler said he can't speak for National Review, but would still rather vote for Trump, if he becomes the Republican nominee, than any of the Democratic candidates, and would "sleep quite happily" after doing so.
"An election is a choice between two individuals," Fowler said. "What we’re doing today at National Review, yesterday and today, is not about making a box choice. It's about defending conservatism."
Also on HuffPost: