Secretary of State Rex Tillerson arrived in Moscow on Tuesday to face what might be his toughest test yet as chief diplomat as he seeks to convince Russia to back away from its support of Syrian President Bashar al-Assad. The visit, Mr. Tillerson’s first as secretary of State, comes as hopes for a broader U.S.-Russian rapprochement have dimmed and as ties between the two former Cold War foes have further soured over

President Donald Trump’s decision last week to strike a Syrian air base in response to Mr. Assad’s suspected deadly chemical weapons attack on April 4. He arrived Tuesday following a two-day stop in Italy for a meeting with top officials Group of 7 member countries—the U.S., U.K., France, Germany, Italy, Canada and Japan. Before leaving Italy, he issued a new U.S. demand for the eventual removal of Mr. Assad, who is blamed by the U.S. and West for the long-running civil war in Syria. READ MORE