U.S. Defense Secretary Jim Mattis praised Vietnam on Wednesday for adhering to sanctions against North Korea, saying at the start of a two-day visit to Hanoi that its leadership on the issue came despite the costs associated with lost trade. Mattis and his counterparts are set to discuss freedom of movement in the South China Sea, a region over which Beijing has extended its dominance in recent years, militarizing several small, disputed islands. Washington hopes to draw a contrast between its own approach and those of China – seen as aggressively modernizing its military capacities – and Russia, which has annexed parts of Georgia and Ukraine. Just two days before Mattis visits, Russian Defense Minister also visited Vietnam, seeking to expand military ties with Moscow’s Cold War-era ally. Sergei Shoigu hailed Vietnam as a “reliable longtime friend” during the talks in Hanoi.