musk and trump are not attacking each other directly....how often does this happen? even trump's PR lie multiplier and axeman leavitt, who attacks the smallest perceived slight to trump, is trying to giggle it off.

Right. That supports the point that I was making earlier - that Musk can really hurt Trump if he wants to. Why else would Trump be handling him with kid gloves, when he never does that with people who defy him? That's how we know that Musk can damage Trump, if he decided to do that. I agree that Musk hasn't yet chosen to go after Trump personally. But he is screwing around with Trump's most important, and perhaps only, legislative priority.

given trump's ability to deflect blame where he likes, i am unclear budget delay blame will fall only on musk (but probably biden), nor how much it really hurts trump unless the delay extends into 2026.

It hurts Trump because it denies him things he needs. It's not a question of blame, it's a question of substance (rare, I know, but it happens).

Trump needs more funding for ICE in order to achieve his immigration enforcement goals. Miller's whipping ICE to the limit, they're pulling in resources from both the rest of law enforcement and the military, they're possibly already spending money they don't have appropriated, and they're still not getting anywhere close to where the Administration wants to be. And it's because they don't have the money to do it. Trump very much wants to go into the midterms having actually fulfilled his promise to dramatically increase the number of people arrested and deported from the interior, and he's not going to be able to do that unless he gets the OBBB passed relatively soon.

He also needs the tax rates extended and the debt limit increased. Failure to get those done with only GOP votes will be a big blow to Trump's agenda. Because all that is lumped into the OBBB (hence, the "O"), it's an all or nothing proposition right now - so the GOP has kind of boxed themselves into fighting about Medicaid and SALT rather than taking those things on their own.