Christian Leuprecht, The Globe and Mail (Canada)
Less than a month out from the NATO allied leaders’ summit in London, the transatlantic alliance is confronting its greatest threat: from within, not without. For a change, though, it’s not U.S. President Donald Trump at the heart of the controversy, but French President Emmanuel Macron, who recently quipped that NATO is “brain dead,” and Turkish strongman Recep Tayyip Erdogan.