Back when Rand Paul seemed like he might be a more popular politician, I spent some time thinking about what he’d need to do to win the Republican nomination. Obviously, if he was going to succeed, he was going to need a new coalition of voters. And, whenever a party adds a new kind of voter, it’s apt to lose ones that were previously in its camp. For Rand Paul, if he brought in non-interventionists, that was going to cost him the neoconservatives.

My point here isn’t that Rand Paul could have ever pulled this off and won the nomination. But I foresaw that, given a choice between Rand Paul and Hillary Clinton, neoconservatives would opt for Clinton.

And this isn’t a knock on Hillary Clinton or any kind of endorsement of Rand Paul. It’s really just a simple observation. If the Republican Party becomes an unfriendly host for interventionists, they will leave the Republican Party.

Perhaps I put that a little too strongly. Whether someone leaves a party or not usually depends on more than just one factor. For neoconservatives, however, foreign policy has always been their prime motivator for political action.

Much has been written about the genesis of the neoconservative movement, and I don’t need to rehash that here, but it’s important to remember that they began as Democrats. They broke with Democrats during the late-1960’s and early-1970’s over the war in Vietnam, relations with Israel (particularly the reaction to the 1973 war and its immediate aftermath), and posture towards the Soviet Union. For the Jewish members, there was also some backlash against what they perceived as anti-Semitism in the New Left, including from the Black Power movement.

Prior to these ruptures, however, they had been strong New Deal Democrats and supporters of the Civil Rights Movement.

Over time, neoconservatives have lain down with dogs and gotten up with fleas, and their betrayals of their liberal roots and initial embrace of multiculturalism are too numerous at this point to document. But these were often matters of making alliances of convenience rather than true sympathies. Neoconservativism arose in New York City intellectual circles, and they’ve never been truly comfortable with Redneck politics or values.

And, when they look at Donald Trump, a New Yorker who is the furthest thing from a Manhattan intellectual, they see way too much Redneck.

In crafting an open letter in opposition to Trump’s candidacy, they are demonstrating that they’re ready to bolt the Republican Party. And it’s not just because they dislike Trump’s very inconsistent isolationism. They don’t like his illiberal attitudes about race, religion, a free press and human rights. They don’t like his cuddly attitude toward Vladimir Putin or his insults towards Mexico’s government, and they are appalled by Trump’s inability to understand that anti-Islamism makes it impossible to have any allies at all in the Middle East. They also just have a visceral distaste for his anti-intellectualism.

Their itemized objections to Trump are things that most liberals agree with or mostly agree with.

Now, this presents more than one interesting avenue for discussion. A lot of people will focus on a simplistic dichotomy here. If neoconservatives are more comfortable in the Democratic Party, that’s an indictment of the Democratic Party. Basically, whichever party they choose is the lesser for it. But, as I’ve said, this is a more complicated defection (or potential defection) than that. War-Hawkery isn’t the only factor here, and Donald Trump often says things that are more bellicose and hawkish than anything a Democratic politician would ever say.

It’s easy to look at the neoconservative record of immorality, violence and failure during the Bush Era and turn them into caricatures of pure, thoughtless evil. If you do that, however, you won’t understand why so many of them are drifting away from the Republican Party.

So, one way of looking at this is to ask what it means from an ideological standpoint and how it might affect U.S. foreign policy and the politics of the Democratic Party, or the next (Democratic) administration.

Another way of looking at it is from a purely political point of view. What happens when a major party has the bulk of its foreign policy establishment either defect to the other side or sit an election out? What’s the political impact of that? Does it foretell a landslide election?

I’ll just say this: as I’ve tried to examine this crazy political environment, I’ve looked for signs of realignment. These are things I’d expect to see if there is going to be a landslide election. One of the things I thought I might see is a mass defection of neoconservatives. I initially thought this would only happen if Rand Paul somehow caught fire (which I never thought was likely), but I’m seeing it now with Donald Trump.

And, frankly, the reasons are quite a bit deeper than they would have been with Rand Paul. With him, it would have been almost exclusively about foreign policy. With Trump, it’s about much more than that. It’s about basically every value they hold dear.