Leading negotiators for the U.N.'s nuclear watchdog agency left Tehran this morning after another round of talks with Iranian nuclear inspections accomplished absolutely nothing. Herman Nackaerts of the International atomic Energy Agency arrived Vienna this morning to report that no progress had been made on an agreement to inspect Iran's nuclear energy sites, and there were also no plans made for future talks. Nackaerts and his team had been hoping to get a look at the Parchin nuclear facility, a military site that inspectors believe has been used or could be used for weapons tests, but he told reports that they were once again denied access.

This is just the latest in a string of frustrating failures for the U.N. agency, which has continued to push for more openness from Iran, but has been met with nothing but delays and denials. Iran has told the IAEA that it was installing new equipment to produce enriched uranium—The Washington Post reported just today that they're hoarding centrifuge magnets—while also announcing that it would convert some of its stockpile to reactor fuel (which makes it useless for nuclear weapons.) However, without the open inspections it's nearly impossible to gauge the true strength of their program or how close they actually are to having a bomb.

Some analysts believe that Iran is attempting to get its program as close as possible to a nuclear weapon—by installing new equipment and setting aside fuel—without actually taking the final step of producing the highly-enriched uranium needed for a working weapon. By keeping its uranium stockpile low, while continuing to develop the technical processes to convert it, they can hold off the day when Israel or the United States might feel it needs to attack. At the same time, they can also keep the program "on alert" and ready to move toward weapon building at a moment's notice. Meanwhile, diplomats drag their feet on negotiations with the rest of the world.

A new round of "six party" talks (independent of the IAEA inspectors' work) are scheduled to begin later this month, though we wouldn't expect much progress on that front either. As we pointed out with North Korea earlier this week, the six major nuclear powers have to little to offer Iran that would outweigh the chance to make their own nuclear bombs. Despite suffering under years of harsh sanctions, they strategy of talking, denying, and delaying does not appear to have changed.