Lionel Barber is former editor of the Financial Times. He is author of "The Powerful and the Damned: Private Diaries in Turbulent Times."
Angela Merkel, Germany's chancellor, has been a permanent fixture on the international stage for the past 16 years, a steadying presence in times of crisis. Her decision to step down after the Sept. 26 general election leaves a vacuum in Germany and Europe that will not be filled easily.
