Iran is expanding its already sizable role in Syria’s multisided war in the wake of Russia’s airstrikes, despite the risk of antagonizing the U.S. and its Persian Gulf allies who want to push aside President Bashar al-Assad.

Politicians in the region close to Tehran as well as analysts who have been closely following its role in Syria say a decision has been made, in close coordination with the Russians and the Assad regime, to increase the number of fighters on the ground through Iran’s network of local and foreign proxies.

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