Secretary of State Marco Rubio began his tenure as the top U.S. diplomat on Tuesday by pledging to keep his department at the heart of U.S. foreign policymaking and execute what he said was President Donald Trump's aim of promoting peace through strength. Rubio noted the department’s new direction will require replacing some priorities, deemphasizing some issues, and eliminating some practices. For details on the new objectives, we spoke with Daniel S. Hamilton is a nonresident senior fellow at the Brookings Institution’s Center on the United States and Europe, president of the Transatlantic Leadership Network, and senior fellow at the Foreign Policy Institute of Johns Hopkins University’s School of Advanced International Studies.