Like so much of Trump's career it's a shit show of epic proportions.

Not only did Trump give the store away ['ghost writer' got cover credit and 50% of the money, an unprecedented deal in publishing] the writer has been talking about how dumb Trump is ever since.

We may first need to answer the simpler question: "Did he ever read?"

He can read? /s

With Trump and his dumb asf cronies at the wheel, it may well be that they simply thought they could strongarm Iran into making a new nuclear deal with Trump's rubber stamp on it, but lacked the ability to see any consequences beyond that. Because, y'know, it's Trump, and any responsible adults in the room left during his first term.

The US has been sabre-rattling about Iran for decades but they didn't attack for the reasons you stated. However, right now the guy calling the shots in America is just that stupid, and he surrounds himself with people who are either as stupid as he is or abject cowards who won't oppose him.

I refuse to believe they wouldnt have seen this coming and the affects it could have.

You are operating on the wrong assumption that politicians are always rational, which is not always the case. The difference this time is that irrational actors are in charge, i.e. the Trump admin.

I refuse to believe they wouldnt have seen this coming and the affects it could have.

Who is they here?

Usually in these kind of situations it goes like this:

Room full of yes men, the dumb boss, and a few subject matter experts and people who know what they are doing.

Those experts aren’t part of the crew, so they don’t fully sense the energy as they are mostly brought in when needed.

Some top military analyst explains the situation and provides best 3 actions, which isn’t met with enthusiasm and after some silence the dumb boss suggests a childish solution, like “why not just attack them until they give in?”

At this point the expert tries to politely explain why that’s a bad idea but is interrupted by the dumb boss followed by the yes men chiming in. The dumb boss makes a decision and the person who knew what they were doing is no longer part of the conversation.

I'm certain you're correct. The US has had analysis that this is what would happen for decades. However, the Commander in Chief (The President of the US) makes the final call for military actions. He infamously doesn't read reports. It doesn't matter how much I formation there is that it would go down like this. If he makes the call they do it, and he's an idiot.

My assumption is that the war simply lets them funnel more money into the military and whatnot, plus being useful as propaganda for the people so deep in MAGA that reality barely matters.

The USA hasn't won a single war since they were part of the Allies in WWII. However you would never know that from US rhetoric. They have used and abused allies every year since to maintain their elevated position in the world which has led to Americans really believing that their washed-up has-been of a country is world best at everything when it is so obviously is not. Trump, being either dumber than the average American, or seeing the opportunity to fleece the American people, or both, bought into the idea that the US could easily overthrow Iran and couldn't understand that it would be the same quagmire that was Iraq, Afghanistan, etc.