Missiles yes, but the payload tech has mostly being shared by NK.  I don't think China is that interested in a nuclear armed fanatical govt who consider them infidels as much as us, but are dependent on their oil with the only thing in common is us as an enemy.  They are happy to keep them armed enough to be leverage on the west, much like NK. But only want them at force parity with their neighbors.  If Russia or China really wanted them nuked up, they would have them by now.  That's not to say they would not ever get or develop them indigenously, but they have to have help in doing so, which NK provides more than anyone else.

China gave the Iranians research reactors and tech expertise in the 90's and direct sales due to economic pressure. China is very much an exporting nation getting rich off other countries, they protect it with fervor. One that we'll see here soon because Iran exported 90% or so of its oil to China.

China has also been using industry contacts to smuggle in nuclear tech and materials well after the sanctions in '97.
https://www.justice.gov/archives/opa/pr/karl-lee-charged-manhattan-federal-court-using-web-front-companies-evade-us-sanctions

Chinese assistance in the development of a uranium conversion facility at Isfaha. Reactor and centrifuge blueprints. After that they're treading grey areas for nuclear "power" use. Over 100 Chinese companies have been sanctioned since 2018 due to infractions of nuclear, drone, and nuclear assistance from Chiona alone into Iran.
https://www.state.gov/wp-content/uploads/2023/08/MASTER-Sanctions-chart-508-Updates-Aug-2023-1.pdf

They never quit; they just made it more of a roundabout issue for Iran getting nuclear capabilities. Sure the Norks have been providing more assistance, more than likely through China and Russia. It benefits the Chinese for the US to put pressure on Iran and NK in the way of trade and tech transfers all while shielding both nations form the UN and other world government entities.

If left alone they might have developed a workable weapon at some point with NK aid,

Or Russia, China, etc. They already have been sold or given missiles by all three in some form.

Welcome from Kentucky!  I'm glad to hear someone is picking up the torch to carry on Murray's good work.  If you're studying under him, you're already lucky.  Murray is a professional and a gentleman to boot, so you're in good company!  Good luck! 

I look forward to giving y'all some business at some point.  Study up on the DM bolt mod! 

Hello everyone! My name is Zach, and through determination and help from above, I am learning how to be a gunsmith here at Murray's. Now as you all know, Mr. Murray is looking to retire. However, I am looking forward to learning from him and you all as well to keep his doors open as he retires. Wish me luck, y'all!

If left alone they might have developed a workable weapon at some point with NK aid, but they were never going to be left alone, although it doesn't help the cause when democrat regimes here fund it for them.  And Israel would not allow them to get one, which is why they have been bombing them periodically for a decade now.  Apparently intel told them the programs were buried deep in a nuke proof bunkers, which is why they needed us and our bunker busters.  I think its arguable they could field a weapon soon much less anytime, but just the material posed a threat being as belligerent as they are and when when they export weapons and tech to groups who would kill anyone on the planet they were pointed at including their Sunni neighbors. 

The ultimate answer is not destroy their weapons, but the regime.  Trump and others sensed an opportunity, and the entire world is probably waiting on the edge of their seat to see if they can throw them off. But despite early success at destabilizing and even decapitating the leadership, the Khomeini regime is still in control.

 And now we see the reprisal attacks from them that have surprised some with their effectiveness to get through our and Israel's top air defense.  And that's just starting.  Sleeper cells active 3rd party groups are now mobilized.  If Trump hoped for a quick win, he's likely to be disappointed.  So the question is, how far do we go, which may be moot, as congress is unlikely to authorize use of force beyond the initial since he ignored them to start with.