China’s navy chief, Adm. Wu Shengli, strolled the Harvard University campus in a tweed blazer and slacks during a visit to the U.S. last fall, joking with students and quizzing school officials about enrolling some of his officers.

A few days earlier, he became the first Chinese navy chief to attend a 113-nation naval forum in Rhode Island, where he hailed U.S.-China military ties and discussed working together on global maritime challenges.

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