With American troops having abandoned Afghanistan, and the Taliban making advances almost every day, Tehran seeks to use the situation to its advantage. Two weeks ago, the mullahs hosted representatives of both the central government in Kabul and the Taliban—while also concentrating troops at the border. It is unclear which of the two the Islamic Republic favors: as a Sunni group ruling a country whose population is between 15- and 30-percent Shiite, the Taliban is a rival to Shiite Iran; but it is also a fellow anti-American Islamist group. Farzin Nadimi analyzes the situation:
Many in [the regime in Tehran] view Taliban control as Afghanistan’s only feasible political option—or, at least, the only option for a friendly Islamic state. This attitude may explain why Iranian weapons have a long habit of showing up across the border. Many such weapons have been confiscated from the Taliban over the years, and although Tehran may or may not have supplied them directly, at least some of them bear strong lineage to those found among Shiite groups in Iraq during their 2005-2011 insurgency.
Tehran respects the Taliban’s resilience, and notwithstanding their ideological differences, they have a lot in common, including their radical views and hostility toward the United States. This affinity could pave the way toward future strategic cooperation, provided the Taliban is willing to give credible guarantees for safeguarding the interests of Afghan Shiites.
Iran’s recent military movements on the Afghan border may just be a precautionary defensive measure; alternatively, they could constitute preparations for a cross-border incursion. Serious consideration should also be given to the possibility that Tehran envisions the “Syrianification” or “Iraqification” of Afghanistan, perhaps by using proxy militias to set up a Shiite safe-haven in the Herat province and elsewhere. Over time, such a strategy could produce a powerful, Iranian-supported military force in parallel to the Afghan security forces, much like what has happened with Iraq’s al-Hashd al-Shabi.
Read more on Washington Institute for Near East Policy: https://www.washingtoninstitute.org/policy-analysis/iran-sets-its-eyes-afghanistan