Oh, it is extremely simple. What, you think the CIA has special info on Iran that nobody else can get? Yeah, they do, but it isn't the kind of meta stuff we would even concern ourselves with.

Basically Iran is one of the last 3 major countries without a foreign, private central bank. It is also a major oil producer. AND it is in the process of setting up an international commerce system that doesn't rely on the US Dollar, along with China, Russia and others.

Once that happens, and they can trade using their own currencies instead of paying a "commerce tax" to the USA, the world will follow suit, ESPECIALLY the Euro zone. Then the US Dollar will be priced fairly, close to zero.

So that's the reason for the sanctions on Joe Average who happens to liver there, making his life hell. Now sanctions are designed to make the ordinary people's lives so hellish that they revolt and topple their own government. But this would never work in Iran because life is good there, no matter if they are now suddenly poor because of US sanctions.

No, the real reason to not bomb them is to avoid starting WW3. Iran is allied with Russia and China, both of which would EASILY provide nukes for the Islamic republic if it were bent on having them. And now they are being forced to develop them themselves because of US aggression, as a deterrent. See, it's one thing to buy a nuke or 12 from friends, and it's another to have a full nuclear armament program. Now they are forced to do just that.

But whether they have homemade nukes or not, it does not matter. Attacking Iran means attacking Russia and China, among others. And this time it wouldn't be a simple proxy war like it was with the US debacle in Syria. It would likely be full-on, troops-on-the ground, cruise missiles, tanks, planes and ships, and so on. And the problem with that is that the USA has dominance, at least in numbers, on tanks, planes and ships.

So, easy win? Not quite, you're forgetting the nukes. The USA has repeatedly said that a nuclear first strike on their part is ALWAYS AN OPTION. This saber-rattling probably gets on other nuclear powers' nerves a lot. What happens when a conflict erupts and because of their geography, Iran, Russia and China are losing the naval war? Would nukes be an option? That's the question isn't it? Think about it: a fleet is a perfect target for nukes: no civil casualties to speak of. It is nowhere near on the same scale as nuking Hiroshima or Nagasaki for example.

Now please consider that at least one nuke was used in Yemen, and it seems nobody knows whose it was, and one in the Ukraine during the coup and again it is uncertain whose it was. So... Small yield tactical nukes ARE being used and of course never reported on by the big news agencies "for state security reasons" or whatever. So if you think a nuclear WW3 is highly unlikely, think again.

But the hawks in Washington are trying to drum up support even for that, with development of a doctrine that says that even a nuclear world war would be "winnable for the USA". Like, lulz.