Although Russia has not directly intervened in the US-Israeli war with Iran, the conflict has underscored the nature and extent of its strategic partnership with the Islamic Republic. Moscow has provided Tehran with satellite targeting data for strikes on US forces as well as delivered advanced fiber-optic drone technology. It has amplified Iran’s propaganda campaign against the West, while benefiting from the war’s spillover effects. The Russia-Iran axis poses a real threat to the US and its allies; it demands a coherent and resolute response. Why It Matters for the US Russia is arming Iran. Russia has a long history...