In today's Washington Post there is mostly sensible column by Zbigniew Brzezinski (he engages in some unnecessary Russia-bashing, although I am no fan of Putin's recent anti-democratic conduct). In it he argues that as it did with North Korea, China may well be able to serve as a negotiating conduit between the US and Iran. He reports, after visiting China, that they accept the Iranian claims that they are not currently actively pursuing nuclear weapons, and that a reasonable and mutually face-saving agreement is possible, assuming that the the US does not push too hard to an unavoidable military option by insisting on sanctions against Iran that will not work and will only push the Iranians towards building nuclear weapons, rather like the stupid Bush policies against North Korea led to that outcome, with more recent reasonable policies having been brokered significantly by China.
It is worth remembering how badly Bush screwed up with North Korea. Clinton made a deal with the North Koreans that they would shut down plutonium production, which they did, although we were not fulfilling our side of the deal fully. North Korea continued to enrich uranium, as Iran is doing, not explicitly part of the deal, although the Bush people declared it a violation when it was revealed, even though now it is recognized it was not at a level to lead to nuclear weapons. Two months into Bush's first term, South Korean President Kim Dae Jung visited the White House, and after being assured by Colin Powell the administration would continue to follow the Clinton policy, was suddenly rebuffed and humiliated when Bush changed his mind under the influence of Cheney and Rumsfeld, who argued that a tough policy would bring the collapse of the North Korean regime. Instead, the South Koreans now hate our guts, and the North Koreans withdrew from the NPT, restarted their plutonium production, and built and tested fission bombs, all without their regime collapsing. After much effort, especially with the help of the Chinese, we are now back to something like what Clinton had achieved, except that now the North Koreans have nuclear weapons.