The 2015 Iran nuclear deal's only purpose is to shield Iran until they have nukes. And really, a deal is as good as nukes for deterring Western military responses to Iranian aggression.
See? This is a problem with the 2015 Iran nuclear deal:
Iran has agreed to sit down with international technical experts investigating the discovery of uranium particles at three former undeclared sites in the country, the head of the U.N. atomic watchdog said Thursday, after months of frustration at Tehran's lack of a credible explanation.
Even when Iran is caught cheating, nothing happens without Iran's cooperation. And why wouldn't Iran expect to get away with this behavior:
The agreement came as three of the remaining signatories to the 2015 nuclear deal with Iran — France, Germany and Britain — backed off the idea of a resolution criticizing Iran for its decision to start limiting access by International Atomic Energy Agency inspectors to current facilities.
This weakness in the deal has long been obvious. Iran can drag this process out with meetings until ... Iran has nukes.
Honestly, if Iran wants a shield to prevent Western military action in response to Iranians conventional, irregular, and terror aggression, a nuclear deal is nearly as good as having nukes. Maintaining the deal becomes more important to the West than stopping Iranian aggression.
Persians are stereotyped as fantastic hagglers. What if Iran doesn't want nukes? What if Iran only wants the West to fear Iran wants nukes and so believe anything Iran does short of building nukes is a glorious victory of Western Smart Diplomacy? I've mentioned this angle long ago, but can't find a post.
This essay bolsters a couple of my points. Iran will demand much in talks from Biden.