The Obama administration is urging US senators to support a new 30-year agreement with China on civilian nuclear cooperation. That’s despite lingering concerns that Chinese companies are exporting sensitive technology to Iran and North Korea. Assistant Secretary of State Thomas Countryman told the Senate Committee on Foreign Relations that China’s nonproliferation record has “improved markedly” since the last agreement was signed in 1985, “though it can still do better.” The current agreement expires at the end of the year.