I can't make sense of your logic here.
Why would the DPRK selling Iran a nuke be at odds with their own behavior ? What behavior ?
Why would the DPRK selling a Nuke bring destruction to the DPRK ?
And why is my point another reason to question having the IRGC in place?
The whole point of MAD is that it is supposed to prevent total destruction.
Going by memory here so happy to be corrected. Think back to Reagan and star wars. The USSR objected because they said it changed the terms of MAD. Because if the US could intercept Soviet Missiles in space, then it would put the US in a potential situation where it could attack first and destroy an incoming soviet reply. So it changed the balance of power such that MAD might not apply.
And FFWD to today with the Patriot and THAAD systems. This has also changed the balance of power. It has meant that ballistic and cruise missiles can be considered ineffective when used against the folk with interceptors. And I would argue that has contributed this war kicking off. Because Trump and Netanyahu appear to consider themselves invincible, because they have the power.
But the weak point with interceptors is numbers. And Iran (PRC also) developed a doctrine of having loads of missiles. Have more missiles than the other side have interceptors. And at the moment, with Iranian missiles getting through Israels Iron dome, and Trump now hyper panicking, that doctrine appears to be effective.
But ICBMs are different. Because physics. To get the range they need to go high into space. And space is big, re-entry speed is about Mach 15, so MAD still applies. ICBMs can't really be defended against.
For sure one could argue that a nuke could be fired on a normal ballistic or cruise the 1000 miles or so at Israel. But given that each warhead can take decades to make, the chance of one missile getting through against THADD would be low. And yes, they could fire loads of missiles to use up the interceptors and THEN fire their nuke.... BUT...
would MAD still not apply ?
That is, if Iran did use a nuke, then it would be replied to with nukes.
It's a flawed system for sure, and I don't want to see nuke proliferation, and Iran should not have them.
But for me, the way to prevent them getting a nuke is not to flatten the place, and say you will keep flattening them... just in case. At some point people need to talk again.
Pakistan has Nukes, India, DPRK, PRC, Russia too, and the thing that stops them using them is MAD. And it can also be said that MAD prevents large scale conventional wars.
But if Iran faces the prospect of a large conventional war every few years against nations who are not willing to talk to them, and who rip up existing non nuke deals , does that not actually incentivize them to get nukes, by any means possible ?
After all, they see DPRK, Russia and Pakistan, pretty much untouchable because of MAD. So are they not more likely to want join that club if a US election can result in an unstable genius in the WH, who is escalating a war he started to try flatten them anyway ?
MAD has worked so far. And yes, Iran should not get nukes. Nobody else should get them. But goodness me, Trump is doing a good job of making people want to have them.
If Iran did buy a nuke from the DPRK, would that not instantly put them into that club ?