Treasury Secretary Janet Yellen’s two-day engagement with top officials in Beijing offered a way for the U.S. and China to contain damage in their economies from the two nations’ intensifying rivalry. While on the military side, there’s been no resumption of bilateral communication — amid risky encounters between the two sides’ air and maritime forces — Yellen’s high-profile visit suggested hope for guardrails in economic competition. In 10 hours of meetings Friday and Saturday, Yellen said she sought to convince China’s newly installed economic team that the U.S.