Due to crushing UN economic sanctions did Iran agree to the JCPOA in 2015. Iran’s economic situation was such that Iran’s leaders agreed to defer the timeline of the Khomeinist apocalypse. Today in contrast there is no such incentive as Iran is able to export oil to China, and Tehran rightly sees no economic benefit in temporary sanctions relief as the next Republican administration would reimpose sanctions and so why on earth would foreign companies be interested in investing in or forging long-term trade ties with Iran? They would obviously not and the regime understands that, but Rob Malley for some inexplicable reason does not.
Therefore the Iranian regime sees no reason to pay a price in return for receiving effectively nothing. The Khomeinist regime considers the development of its nuclear weapons program inextricably linked to its planned apocalypse. Nuclear weapons would give Iran the leeway to attack other nations with weapons of mass destruction with nuclear impunity. If it is prevented from developing nuclear weapons will Iran unleash the WMD apocalypse anyway in response to Israel and America destroying its nuclear weapons program.
Tehran’s motivations are apparently little understood by the international community, including in Washington. Why defer the reappearance of the Hidden Imam unless you absolutely have to? Then of course it could be argued that the Hidden Imam could be provoked into reappearing even earlier by an Iranian preemptive wave of WMD attacks around the world and not wait until the Iranian nuclear weapons program is destroyed by Israel and America. This ignores that Iran has both defensive and offensive considerations and that its nuclear weapons program is both offensive and defensive. Tehran of course is not absolutely convinced that WMD attacks will prompt the Hidden Imam to reappear, but they are hopeful that it will work.
What the regime is convinced about however is its own righteousness and that the dystopian trajectory of the Islamic Republic of Iran is indeed the early eschatological process of humanity. Try putting yourself in the shoes of the octogenarian Supreme Leader Ali Khamenei, he apparently believes that it is realistic to expect the reappearance of the Hidden Imam within Khamenei’s own lifetime. Why on earth would he defer this unique event to the next supreme leader if such deferral offers no tangible benefits for Iran and certainly is not required by economic or other necessity? The truth is that America has nothing to offer Iran.