David McKeanDavid McKean is a senior fellow at the German Marshall Fund. Formerly he served as director of Policy Planning at the U.S. Department of State and as U.S. ambassador to Luxembourg.Bart M.J. Szewczyk is adjunct professor at Sciences Po i Paris. Formerly he served on the Policy Planning staff of the U.S. Department of State and as adviser on global affairs at the European Commission's think tank. Read More Read Less