Billionaire Elon Musk’s breakup with president Donald Trump, a feud that’s been many months in the making, has become almost indescribably messy.

In public, the pair have mainly butted heads over Trump’s tax bill, which is expected to add trillions of dollars to an already colossal mountain of debt.

Musk has excoriated the bill as a “disgusting abomination,” ominously calling for any Republican lawmakers willing to support it to be “fired” during next year’s midterm elections.

As a move that’s widely been seen as retribution, the White House unexpectedly announced over the weekend that it’s pulling Jared Isaacman’s nomination — Musk’s personal pick — for the role of NASA administrator. In a baffling statement at the time, the White House said Isaacman wasn’t in “full alignment with” the Trump agenda.

If the move was intended as an attack on Musk, it succeeded. As the Wall Street Journal reports, the move has “infuriated” the richest man in the world, who’s been seething privately to his inner circle that the hundreds of millions of dollars he paid to get Trump elected didn’t even buy him the privilege of picking the next NASA head.

Looking past the astonishingly oligarchical thesis that a billionaire opening his checkbook should automatically allow him to pick key members of government, the episode also illustrates Musk’s increasingly shaky sense of strategy.

Trump has long been known for his pettiness, arrogance, and shifty sense of allegiance; absolutely nobody should be surprised, at this point, when an attempted alliance with the longtime reality TV star doesn’t work out the way it was intended.

Nobody knew this better than Trump’s own staff at the White House. According to the WSJ, they were attempting to bury the hatchet before Musk made his departure, and part ways on good terms.

But given Musk’s latest comments, those efforts appear to have been in vain.

Besides fuming over losing hand-pick to control NASA, Musk has plenty of other reasons to hop off the Trump train to refocus his efforts on his businesses. For one, he has done incredible damage to his carmaker Tesla, which is still reeling from plummeting sales worldwide. SpaceX is also seriously struggling to make progress on its enormous, Mars-bound Starship rocket.

Meanwhile, the real motivation behind Isaacman’s dismissal hasn’t flown over the billionaire space tourist’s head.

“I had a pretty good idea, I don’t think the timing was much of a coincidence,” Isaacman told Ars Technica. “Obviously, there was more than one departure that was covered on that day,” he added, likely referring to Musk.

“There were some people who had some axes to grind, and I was a good, visible target,” he added.

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