It's disappointing that negotiations on Iran's nuclear program failed to produce a final agreement by Monday's deadline. But the decision by Iran and six world powers to keep talking is vastly preferable to the alternative. A rupture in the negotiations would have freed Iran from its commitment — which the International Atomic Energy Agency says Tehran has honored — not to accelerate its efforts to develop nuclear energy while negotiations proceed.
Moreover, both sides indicate that there was progress in recent weeks toward the ultimate goal: a permanent agreement under which Iran would credibly agree to use nuclear power only for peaceful purposes in exchange for the lifting of sanctions that have damaged its economy. Secretary of State John F. Kerry said that negotiators for Iran and the so-called P5-plus-1 — the five permanent members of the U.N. Security Council and Germany — "now see a path for solving issues that until now were intractable."
This isn't the first extension of the talks, which originally had a deadline of July 20. But it has been only a year since Iran and the P5-plus-1 unveiled a Joint Plan of Action designed to end years of diplomatic stalemate over Iran's nuclear program. Iran shouldn't be allowed to stretch out the negotiations indefinitely, but the seven-month extension announced Monday is a reasonable one.
That doesn't mean an agreement is inevitable. And even if one is reached by negotiators and ratified by President Hassan Rouhani, religious leaders in Tehran might sabotage it. But that is no reason to stop talking, especially when there are prospects for success and grave consequences for failure.
One of those consequences could be yet another U.S. military intervention in the Middle East. Last year, President Obama said he would "take no options off the table, including military options" to ensure that Iran didn't develop nuclear weapons. We agree with the president that a nuclear-armed Iran would be a deeply destabilizing development (even if it didn't use a nuclear weapon against Israel, a highly unlikely scenario given Israel's own nuclear arsenal). But military action by either the U.S. or Israel against Iran would provoke convulsions in the region that would endanger American lives as well as American interests.
Members of Congress, including the new Republican leaders of the Senate, need to keep that scenario firmly in mind if they are tempted to interfere with the negotiations by passing new sanctions legislation before the extended talks have run their course. This is not a matter for political gamesmanship.