THE MOST interesting public result of the latest talks with Iran on its nuclear program was the claim by Tehran’s chief negotiator, Saeed Jalili, that the new negotiating proposal from the United States and five partners was a possible “turning point” in what has been nearly a decade of fruitless diplomacy. Those cheery words, and the Iranian’s quick agreement to two follow-up meetings in the next five weeks, raised the question of whether the regime is positioning itself to strike a deal that would freeze the most dangerous elements of its nuclear work in exchange for an easing of the sanctions that are choking its economy.

We hope that is the case. Unfortunately, an equally plausible explanation for Mr. Jalili’s comment was that he was celebrating the fact that, in the eight months since Iran last agreed to meet with the international coalition, the offer to Tehran had grown more, rather than less, generous. “It was they who tried to get closer to our point of view,” he crowed, while adding that there remained “a long distance to the desirable point.”

U.S. officials denied that the terms offered Iran had grown softer as the regime has refused talks, stonewalled international inspectors and continued to defy U.N. Security Council resolutions by adding to its stockpile of enriched uranium. But it certainly looks that way. While the previous proposal of the five Security Council members and Germany, in Baghdad last May, called for Iran to shut down an underground nuclear plant known as Fordow and to ship its stockpile of medium-enriched uranium out of the country, the bid made in Almaty, Kazakhstan, scales back the Fordow shutdown to a suspension of operations and allows Iran to retain some of that 20 percent-enriched uranium.

In part, this shift can be seen as a response to a changing situation: Iran has been converting some of the medium-enriched stock into fuel for a research reactor, giving it a pretext to refuse a previous scheme under which uranium shipped out of the country would have been returned as fuel rods. But the coalition also appears to have offered a greater easing of sanctions — though officials said measures directed at Iran’s oil industry and financial system would remain intact.

If Iran altered its own, unacceptable proposals from previous rounds, there was no indication of it in the accounts of either side. That raises the possibility that the regime will simply pocket the easier terms and return to its stonewalling, with the expectation that another crumbling of the coalition position will ensue. In recent months, Tehran has avoided crossing Israel’s red line for military action by keeping its stockpile of ­medium-enriched uranium below the quantity needed for a bomb, but it has also begun installing a new generation of centrifuges, which could move it much closer to a breakout capacity. Maybe these zigs and zags, like Mr. Jalili’s declarations, are the prelude to a compromise. But history suggests they are the tactics of a regime convinced that it can outlast and outmaneuver the United States and its partners.