We may be witnessing the collapse of the Republican party, or at least the Republican party as we know it. And if so, then Donald Trump is the harbinger of its apocalypse.

The signs of the party's weakness and disarray are everywhere. Trump is the GOP's presidential front-runner by most any measure: FiveThirtyEight, which recently published a long essay looking at the GOP's breakdown as a party, gives him a 55 percent of winning the nomination, based strictly on the polls. Yet the candidate is now in open warfare with two of the right's most influential media platforms: National Review and Fox News.

Last week, National Review published a special issue devoted to denouncing the candidate, with an unsigned editorial labeling him a "a philosophically unmoored political opportunist who would trash the broad conservative ideological consensus within the GOP in favor of a free-floating populism with strong-man overtones."

Then on Tuesday, Trump announced that, because Fox refused to comply with Trump's demand that moderator Megyn Kelly—who has feuded with Trump for months—be removed, he would not participate in the network's forthcoming presidential debate.

National Review isn't the party, of course, and neither is Fox, but they are important player on the right, and they wield considerable influence within the Republican party.

Some level of friction between candidates and right-leaning media is fairly common, and both Fox and NR have certainly criticized GOP candidates before. Even still, this sort of sustained, all-out conflict between two of the right's leading media outlets and the GOP's presidential frontrunner is virtually unprecedented. Among other things, it suggests that the traditional party power structures are breaking down, and are now competing amongst each other to retain their dominance.

Trump's candidacy exists almost entirely outside the traditional support structure for successful Republican candidates. His campaign, for example, is run by a small staff of loyalists with little traditional national campaign experience and funded without the backing of the GOP donor class. He appears to have only one issue adviser, a former trade and immigration staffer for Alabama Sen. Jeff Sessions, who only came on board last week. As Dan Drezner notes, despite months of promises to bring foreign policy advisers on board, Trump has yet to do so; instead, he has suggested that he is receiving counsel from people who, when asked, say they've never spoken to the candidate.

Trump is essentially running his own party now, housed within a hollowed-out GOP brand. In less than a year, he has all but taken over.

And even as media and intellectual wings resist Trump's takeover, official party organs are allowing—arguably even encouraging—him to proceed. Shortly after National Review published its anti-Trump package last week, the Republican National Committee (RNC) informed the magazine that it had been booted from a spot co-hosting a GOP debate next month. This week, the RNC, which sponsors and helps organize the debates, said it would not get involved in the matter. Fair enough, in some ways: Candidates can choose for themselves whether to participate. Yet it is an admission that it will allow Trump's no-show tantrum without complaint. And, of course, the RNC will support Trump if he becomes the nominee.

Other parts of the party apparatus appear willing to go along with this as well. Trump is far from an establishment figure, and yet figures from the party's establishment—an overused and under-defined word that mostly just means the leaders and actors who help guide the party's course—seem increasingly willing to follow Trump. Prominent GOP Sen. Orrin Hatch recently said he's "come around a little bit on Trump," and mused that Trump might actually expand the GOP's appeal. Former presidential nominee Bob Dole recently argued that Trump could "probably work with Congress, because he's, you know, he's got the right personality and he's kind of a deal-maker." Multiple reports, based on interviews across the country, suggest that GOP donors and other influencers have begun to warm to Trump, and are in some cases have begun to reach out in hopes of contributing to his campaign.

This is what a failing institution looks like: leaderless, directionless, torn by infighting between its power centers, and willing to sign on to anything or anyone that will provide some semblance of purpose or momentum.

True, Trump may not succeed in capturing the nomination, and the party may well hold together in some form or fashion. But if that is the case, then we have learned something anyway.

Mainly, the ease with which Trump has made his moves suggests the poor state the party was in to begin with. Part of what Trump has accomplished, appropriately enough, is to expose the depths of the party's weakness, both in terms of organization and ideology. The GOP can rally no one to its cause because it does not really have one—or, at minimum, does not have one that motivates a sufficient number of people.

For many prominent Republicans the party's purpose is mostly transactional, hence Dole's argument that Trump might be an effective dealmaker, and the pursuit of Trump by previously put-off party donors, who seek to buy a stake in his campaign, and establish influence accordingly. Perhaps inadvertently, then, the GOP establishment is proving Trump right that the party exists largely for self-perpetuation and self-protection.

At the same time, the success of Trump's particular campaign has revealed the deep strains of nativism—shading into outright racism—that runs through segments of the American right, and its friendliness toward authoritarian politics.

To the extent that Trump's campaign is about any one thing, it is about fear of foreigners and immigration, and he has stoked fear and anger toward immigrants more overtly than any other popular candidate in recent memory, often through off-handed proposals that stretch the bounds of both the constitution and decency. And Trump's fans love it: His biggest applause line is his promise to build a wall, and at a recent rally the crowd cheered when Trump promised to kill the wives and children of terrorists.

What's more, his supporters frequently go even further than Trump in stating their disdain for immigrants and outsiders. CNN interviewed more than 100 Trump backers recently, and here are some of the things they said (via The Washington Post's Greg Sargent):

"It seems like we really go overboard to make sure all these other nationalities nowadays and colors have their fair shake of it, but no one's looking out for the white guy anymore." "White Americans founded this country. We are being pushed aside because of the President's administration and the media." "Hey, hey. Ho, ho. All the Muslims have to go!" "I don't want them here. Who knows what they're going to bring into this country?" "We can't look at a Muslim and tell if they're a terrorist or friendly."

Trump's campaign has attracted racists and white nationalists. At a rally in Alabama last year, one attendee told The New York Times, "Hopefully, [Trump is] going to sit there and say, 'When I become elected president, what we're going to do is we're going to make the border a vacation spot, it's going to cost you $25 for a permit, and then you get $50 for every confirmed kill.'"

At the same event, another told The Washington Post, "You probably think we're prejudiced, but my whole life we had niggers work for us in the field. And they were niggers. My daddy called them niggers. I'm not ignorant. That's just the way I was raised. There's black people and there's niggers. You live around here, you know the difference." At a Trump rally in Las Vegas recently, a black activist was beaten while onlookers yelled things like "light the motherfucker on fire," and "Sieg heil!"

Not all Trump supporters buy into these sentiments, of course, but the consistency with they pop up amongst his supporters at campaign events, in addition to their prevalence on social media, is telling enough about both Trump and the party he's taken hold of.

The fact the GOP has made such an effective vehicle for Trump's angry, ugly, authoritarian, nativist campaign is both revealing and damning. Trump is using the party as a host body for his antics and ambitions, but he is only able to do so because it was already prepared and ready for someone like him to come along—or perhaps because it had been neglected for so long by self-interested party elites.

The point is that the party was weak before Trump arrived. And in retrospect it's clear that there were signs of its weakness high and low: the emergence of the Tea Party, the constant fighting between party factions, the disinterested and directionless leadership, the perpetually frustrated party intellectuals, the repeated interest in and acceptance of joke candidates, the general disinterest in governance or policy, the cozying up to folks like, well, Donald Trump. All of which suggests that the GOP, if not actively working towards its own doom, was setting the stage for the breakdown we're seeing now.

Trump, then, may be the catalyst for the party's demise, but the Republican party apocalypse was in the works long before he arrived.