As international talks on Iran were about to resume, the Obama administration early this month secretly presented an eight-page document to Tehran in a bid to demonstrate Washington’s flexibility and offer an opening to end the protracted dispute over Iran’s nuclear program. But a week later, the chairman of the Iranian parliament’s nuclear committee went public with the Nov. 9 proposal, slamming it by saying the U.S. had brought the negotiations “back to zero.” The potentially damaging leak by Ebrahim Karkhaneh, the chairman, marked a low point in what U.S. and European officials see as an ongoing, and possibly intensifying, effort by hard-line factions in Tehran to sabotage more than a year of international negotiations […]