Another obstacle is institutional. Given that the United States is the biggest partner inside NATO, the alliance is not a place where allies can plan for any sort of post-American future. “That would defeat the very purpose of NATO,” said one senior alliance diplomat.
Inside the alliance there is no contingency planning for a NATO without the U.S., according to three NATO diplomats. They interpret the signals from Washington not as a prelude to U.S. withdrawal from the alliance but as a powerful wakeup call for Europe as Washington refocuses on the Arctic and the Indo-Pacific.
“The United States and NATO allies take our Article 5 commitments … very seriously,” Whitaker, the U.S. ambassador, said last week. “Article 5 is ironclad.”
“But we have expectations,” he said at the Doha Forum in Qatar, namely “[Europeans] picking up the conventional defense of the European continent.”
A third and particularly daunting task for Europeans would be to replicate or replace military capacities currently provided by the U.S.
Europeans provide up to 60 percent of capabilities in some domains, said Oana Lungescu, a former NATO spokesperson who is now a fellow at the Royal United Services Institute think tank. But in others — such as intelligence, heavy airlift and deep strikes — the United States typically provides an outsized share.