After threatening to veto the latest government spending bill, President Trump reluctantly decides to sign it just hours before the funding deadline. H.R. McMaster leaves his post as National Security Advisor and is swiftly replaced by a former U.S. diplomat considered to have hawkish tendencies. As Robert Mueller's Russia probe continues, a leading member of the president's legal team steps down. Plus -- fears of an international trade war worsen after President Trump announces plans to impose tariffs on China. CBS News Correspondent Steve Dorsey will have these stories and more on the CBS News Weekend Roundup.