Never-ending nuclear talks with Iran are bordering on the absurd

Much has changed in the nearly 18 months since Iran and world powers started trying to salvage their nuclear deal of 2015. Three of the seven parties to the accord have new leaders. A fourth invaded its neighbour. What was meant as a brief run of negotiations became a marathon. Yet negotiators flock back every few months for more meetings at the home of the un’s watchdog, the International Atomic Energy Agency (iaea) in Vienna.