GREGORY B. CRAIG, a partner at the law firm Skadden Arps, has served in key policy positions for much of the past thirty years, including as President Obama’s White House counsel, director of State Department policy planning in the Clinton administration, and senior advisor on defense, foreign policy, and national security issues to Senator Edward M. Kennedy. In 1998, he was named assistant to the president and special counsel in the White House, where he led the team assembled to defend President Clinton against impeachment. Mr. Craig has served as vice chair of the Carnegie Endowment for International Peace and chair of the International Human Rights Law Group.