A leading economist warned on Thursday that the United States and China are in a “conflicted co-dependency” that this year’s two bilateral summits failed to address. “I think there’s a good chance that we’re in a temporarily more stable place. But to say that has solved the deep-rooted problems between us, I think is a real stretch,” said Stephen Roach, a veteran China-watcher and the former chairman of Morgan Stanley Asia, at the China Institute of America. “You mentioned the two summits that...