Iran gains ground in Afghanistan as U.S. presence wanes

In Iraq, it has exploited a chaotic civil war and the American withdrawal to create a virtual satellite state. In Afghanistan, Iran aims to make sure that foreign forces leave eventually, and that any government that prevails will at least not threaten its interests, and at best be friendly or aligned with them.

One way to do that, Afghans said, is for Iran to aid its onetime enemies, the Taliban, to ensure a loyal proxy and also to keep the country destabilized, without tipping it over. That is especially true along their shared border of more than 500 miles.

But fielding an insurgent force to seize control of a province shows a significant — and risky — escalation in Iran’s effort.

“Iran does not want stability here,” Naser Herati, one of the police officers guarding the post outside Farah, said angrily. “People here hate the Iranian flag. They would burn it.”