Donald Trump is threatening a third party run — again. So what else is new?

At a town hall meeting in Mount Pleasant, South Carolina, Trump objected to being booed at the GOP debate in Greenville on Saturday night after having accused former President George W. Bush of lying about WMDs in Iraq as well as blaming him for the attacks of September 11, 2001.

Trump ranted, “The RNC better get its act together because, you know, I signed a pledge. The pledge isn’t being honored by the RNC. I signed a pledge, but it’s a double-edged pledge. As far as I’m concerned, they’re in default on their pledge.”

Of course, Trump was referring to the pledge he signed last September in which he promised not to launch a third party bid for the White House and support the GOP nominee if he did not win the nomination. Trump signed the pledge after drawing jeers at the first GOP debate in August when he said he would not rule out a third party run. To be precise the pledge reads:

I, Donald J. Trump, affirm that if I do not win the 2016 Republican nomination for President of the United States I will endorse the 2016 Republican presidential nominee regardless of who it is.

I further pledge that I will not seek to run as an independent or write-in candidate nor will I seek or accept the nomination for president of any other party.

At the time, Trump also said, “So I will be totally pledging my allegiance to the Republican Party and for the conservative principles for which it stands.” But since signing the pledge, Trump has raised the possibility of reneging on it. In November, Trump tweeted, “‪@WSJ reports that ‪@GOP getting ready to treat me unfairly—big spending planned against me. That wasn’t the deal!” The following month, after the Republican backlash against Trump’s proposed Muslim immigration and travel ban, Trump tweeted, ”A new poll indicates that 68% of my supporters would vote for me if I departed the GOP & ran as an independent.” Given that Trump has already twice threatened to break his pledge, why should anyone be surprised that he would do so a third time?

Yet this time around, Trump’s threat is odd when you consider that he won New Hampshire primary by a 2:1 margin over John Kasich and remains the odds on favorite to win in South Carolina this weekend. A CBS News/YouGov poll released on Sunday (but conducted prior to the debate) gave Trump a 22-point lead over Ted Cruz (42% to 20%). Even if Trump’s anti-Bush remarks do hurt his poll standings, the anti-Trump vote is likely to be fractured. The South Carolina primary remains Trump’s to lose. If Trump wins South Carolina as decisively as he won New Hampshire, it is difficult to see how anyone could stop him from winning the Republican nomination. In which case, why would he need to bring up the pledge at all?

It would seem that winning just isn’t enough for Donald Trump. This, after all, is a man accustomed to getting his way. He wants absolute fealty whether or not he warrants it. But if Trump wants the loyalty of Republicans, then surely he must understand that a previous Republican President, even George W. Bush, is still held with great affection in some quarters. Does he honestly expect that Republicans, be they donors or not, are going to be inclined to react kindly when they hear him claim that President Bush lied about WMDs in Iraq and blame him for the deadliest terrorist attack on American soil? Trump deserved every boo and jeer he got on Saturday night.

Donald Trump signed a pledge to the Republican Party, but he claims the Republican Party made a pledge to him. The Republican Party has no more obligation to Trump than it does to any of his opponents. Marco Rubio, Ted Cruz, Jeb Bush, John Kasich, and Ben Carson understand this very well. But that isn’t how Trump rolls (or for that matter how he trolls). So when Trump threatens to break his pledge he is telling Republicans, “Either nominate me as your candidate or I will run against you.” If Trump is so eager to help Hillary Clinton into the White House then Republicans ought to tell him, “Either are you with us or you are against us.”