Musk just wasn't expecting to start a feud with the guy he put into office with that $200 million. Up until that point though, he was getting literally everything he wanted out of the bribe.

From what I've read Musk believed that the loss of the EV tax credit would hurt the EV programs at other companies such as GM and Ford much more than it would Tesla, with a decent chance it could push the timeline for those programs becoming profitable far out enough that those companies might have to greatly cut back whereas Tesla could still profit without the credit.

If he did indeed believe that then supporting Republicans may have appeared at the time to be in his self-interest. That doesn't mean it was a good idea, of course, because who said that party would stop at just that tax credit? They also killed the emissions credits that ICE car companies were buying from Tesla which were responsible for something like 40% of Tesla's net income.

The $200 million was money well spent, it resulted into Musk staying out of jail and pulling up the ladder behind him now that's he the incumbent. The success or failure of Tesla in the marketplace at some point could have killed Musk's empire but I think we are now past that point: Tesla will survive and more friction for contenders serves him well.

Finally, there is a timing issue here as well: when Musk spent that money he was set to become a favored player at the court of Trump if Trump won, which happened. But that didn't really play out long term in the way he expected. So in a sense you are confusing the position that Musk took prior to Trump's election with the consequences almost a year later, which Musk could not have known with certainty at the time, even if it is a mixed blessing for Tesla, and probably a bigger loss to the challengers rather than to the incumbent.

Electrek chief editor naively thought he would actually get $500K in Tesla supercars from referral program https://electrek.co/2019/01/17/tesla-roadster-free-killed-re...