Because it's not ultimately about beliefs or ideology or philosophy or the team or even the "tribe," but ALL about HIM. The cult of personality, triumphant. If you're not with Trump, you're against Trump, and therefore must be eradicated from the newly re-named T.R.U.M.P.:
This is also old news. Trump has made this going-third-party threat countless times since last summer. And, subtle "gentleman" that he is, that is what made his original gambit - meteor his way into the race, carve out too-large a chunk of the GOP electorate, bolt before actual primaries and caucuses could be held to avoid the embarrassment of defeat, claim the party "establishment" had been "unfair" to him (by not "ensuring" that he would win) and take his supporters with him, splitting the Republican vote and guaranteeing a Sanders or Hillary victory in November - so easily perceivable and deducible. The thing is, the too-large chunk of the GOP electorate he carved out was big enough to dominate the race against a distressingly overlarge field of rivals who shattered the rest of the GOP electorate into way-too-small chunks that couldn't compete with Trump, a dynamic that lingered way too long, a month into the actual primary season, to where the "poor man's Michael Bloomberg" is poised to run away with the nomination. And, of course, split the Republican vote and guarantee a Sanders or Hillary victory in November, but also riv the Republican Party for years to come, or maybe permanently, Whig-like.
Here's the question: Given the roaring success of the Trump invasion angle, why is he bringing up his own independent candidacy as a threat in retort to Marco Rubio pretty much declaring last week that he'll never support Trump? What does he care what Rubio does after he puts the Florida senator away? He's just another "loser," right? Is this just typical Trump thin-skinned egotism, or is he, in the wake of his latest debate meltdown in Houston last Thursday, worried that he might underperform in the "SEC primary" tomorrow?
Looking ahead to November, revisit Jake Tapper's question again: He's asking Trump essentially a unity question: "If you're the Republican nominee, are you going to reach out to conservatives to reassure them and bring them and Trumplicans and "establishmentarians" together?" No mean feat given that every action he's taken since last June has been designed and intended to blast the party apart. And Trump's reaction was typically reflexive: In essence, a big, fat "F.U." to anybody who doesn't close ranks and drink the Trump-Aid.
The antithesis, in other words, of the "leadership" conservatives have been claiming to want, crave, for the past seven years. Which is why I maintain that ex-conservative Trumplicans have not only sold out the principles for which they once claimed to stand, but have given up and for all intents and purposes become their (former) enemies.
And that does not bode well for the general election to come:
In 1972, for instance, about a third of Democrats voted for Richard Nixon rather than George McGovern, who won the Democrat nomination despite getting only about a quarter of the popular vote during the primaries. The Democrats’ tumultuous nomination process in 1968 was nearly as bad, with many defections to both Nixon and George Wallace. The 1964 Republican nomination of Barry Goldwater produced quite a few defections. Primary challenges to Jimmy Carter in 1980 and George H.W. Bush in 1992 presaged high levels of inter-party voting in November....
[T]he degree of party unity during the primaries is one of the better historical predictors of the November outcome. That could be a problem for Republicans whether they nominate Trump or turn around and nominate Marco Rubio, Ted Cruz or John Kasich; significant numbers of GOP voters are likely to be angry either way.
Which was always, and remains, the ultimate purpose of the Trump candidacy - just as Bill Clinton insidiously foresaw.
Here's another harrowingly interesting statistic:
There's not as much parity there as it looks. I think Rubio voters could reconcile themselves to Cruz, and vice versa; but neither will be able to hold their noses, and suppress their consciences, enough to join the Trump cult. And the details of that CNN poll prove it:
Sixty-nine percent of Republicans who aren’t supporting Rubio say they’d definitely or probably vote for him as nominee; the same percentage say so of Cruz. Just 52% of GOPers who aren’t voting for Trump say they’d get onboard the Trump train, though; 13% say they probably wouldn’t support him and another 35% say they definitely wouldn’t. If those last numbers held, you’d have nearly 18% of the total Republican electorate boycotting Trump on election day. [emphases added]
I'm not going to speak to or speculate on the motivations of anybody else, but I can give you mine right here and now: Because in a Trump-Rodham or Trump-Sanders showdown, there will be two Democrats on the general election ballot, the only difference between them that one will have an "R" after his name. And I do not vote for Democrats. Period.
But the greatest and bitterest irony of all to me is that there are former conservatives, former Tea Party purists, who are now rabid Trumplicans, who are already insisting and demanding that we, yes, TRUE CONSERVATIVES jettison those same principles, as they have, and "get with the program". And this fanaticism is every bit as despicable, if not more, as was their erstwhile purity fetishism, the common link that irrational, insatiable, mis-directed anger of which they are so smugly proud.
Trump and his cult definitely deserve each other; but the rest of us sure as heck don't.
UPDATE: Nebraska GOP Senator Ben Sasse: "This is an 1860 moment":
Maybe; I think I know what Sasse is getting at here, but there wasn't one firm date, or year, in which the Whig Party disintegrated; it just kind of slowly faded away over the course of the 1850s after Millard Filmore's infamous slavery "compromise" that the Whig base of that day refused to accept.
I think a more apt comparison is "1964 in reverse"; Barry Goldwater's conservative insurgency taking over what had been Nelson Rockefeller's center-left Republican Party. Only now it's the twenty-first century Al Czervik taking the GOP back on Nelson's Rockefeller's behalf.
And La Clinton Nostra's.
And we all know what happened to the GOP in the ensuing general election, and what the consequences of that were, now don't we?