Now that relationship's gone. Merkel and Hollande sharply disagree about the way forward for Europe. The divergence at the center of Europe has created fresh worries about the continent's fate.
Observers say it can take time to rebuild carefully nurtured national alliances.
"Through their personal exchanges at summit meetings, leaders familiarize each other with the domestic political pressures and constraints they face back home," said David Shorr, an expert on summitry at the Stanley Foundation, an Iowa-based organization that promotes multilateralism. "The personal trust piece of this has to be established freshly with each new leader who joins the club."
But Shorr noted that personal chemistry may count for little when nations start pulling apart on the issues.
"You don't need to know President Hollande well to recognize the French elections themselves as a pretty clear weather vane for the shifting political winds," he said.
Don Melvin can be reached at http://twitter.com/Don_Melvin
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