Emmanuel Macron, the French president, has warned European countries that they can no longer rely on America to defend NATO allies.

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"What we are currently experiencing is the brain death of NATO," Mr. Macron declares in a blunt interview with The Economist.

"Europe stands on the edge of a precipice and needs to start thinking of itself strategically as a geopolitical power, otherwise we will no longer be in control of our destiny," he said.

During the hour-long interview, conducted in his gilt-decorated office at the Elysée Palace in Paris on October 21, the president argued that it is high time for Europe to "wake up." He was asked whether he believed in the effectiveness of Article Five, the idea that if one NATO member is attacked all would come to its aid, which many analysts think underpins the alliance's deterrent effect. "I don't know," he replied, "but what will Article Five mean tomorrow?"