That gold plane and those billions slipped into Jared Kushner's pocket bought them the US military.

Settle scores?
Save face?
Finish it once and for all?
Reclaim land?
Set up for future opportunities?

Logic doesn't always prevail, or at least, it can require some context to follow.

Lot's of reasons to join a dog pile.

But we effectively act as a mercenary group for them and Israel, except we don’t get paid by either (and in Israel’s case we pay them).

I don’t think the Arab states have to do much. If we want to ensure oil flowing (and Asia is particularly dependent on middle eastern oil), the US military will do most of the dirty work.

If Iran’s remaining leadership is dumb enough to actually try to step it up with the Saudis, I think SA will start putting their weapons to use. For now it’s likely deterrence. I have no clue about the other gulf states. I fully expect expect the Houthis to step it up too, so maybe that’s the front Saudi Arabia will take on.

This is looking like the Pandora’s box most dreaded. It was probably bound to open at some point, but either way every member of this administration will likely sleep with one eye open, because Shiite clerics will be issuing fatwas left and right. These folks don’t forget very quickly. Look at Salma. Rushdie. They tried killing him decades after the fatwa was issued.

After Israel took out Nasrallah and Hazbollah it was clear they would settle all scores. The Ayatollha was the biggest. They found a willing henchman in Trump.

Have been trying to get the US to eliminate the Iranian regime for decades. Until now Presidents have been too smart to fight someone else's war.

Since we are doing what they wanted all along I doubt they will join the conflict. If they do I would expect it to be like the Soviets joining the fight against Japan in WW2. Attack a practically defeated opponent for strategic political reasons rather than any military purpose

"security" meaning the relative tranquility and MONEYMAKING they've enjoyed before Trump set fire to all this. They don't have the military infrastructure and means to do much here

the US has lots of "customers" in the Gulf

Through Trump
Will bomb for cash