Washington — Mitigating the malign influence of Iran remains a major US objective in the region, Gen. Joe Dunford, chairman of the Joint Chiefs of Staff, said in an interview this week. Speaking to Breaking Defense contributor James Kitfield, Dunford said, "I haven't seen any change in Iran's behavior. The Republican Guard's Quds Force continues to exert a malign influence in Iraq and Syria through proxy forces and militias, and in Lebanon through Lebanese Hezbollah. Iran's support for (Houthi rebels) in Yemen has also been unhelpful, and Tehran continues to pose a threat to close allies." He said that it was important to "zero in" on one of the most important issues for the United States, "and that's freedom of navigation in the Straits of Hormuz and the Bab Al-Mandeb." "By harassing US and international maritime activities ... and supplying advanced anti-ship cruise missiles to Houthi rebels in Yemen on the Red Sea coast, Iran is posing a threat to two waterways that are absolutely crucial to global commerce." He added: "Since the 1970s and (President Jimmy Carter's ‘Carter Doctrine'), the United States has been committed to keeping those vital waterways open." In January, a US Navy destroyer fired three warning shots at four Iranian fast-attack vessels near the Strait of Hormuz after they closed in at high speed and disregarded repeated requests to slow down.