With a 16-year U.S.-Russia nuclear agreement expiring Feb. 5, three former national security officials testified in front of the Senate Armed Services Committee (SASC) Tuesday to advise on next steps, but two “would not recommend” extending the treaty, while a third, the former U.S. chief negotiator for the New Strategic Arms Reduction Treaty (New START), favors a year-long extension. Signed in 2010 by then U.S. and Russian Presidents Barack Obama and Dmitry Medvedev, the treaty expires Thursday. New START limits…