U.S. President Joe Biden's trip to Asia sought to put on full display the robust bilateral alliances with Japan and South Korea, as well as the evolving partnerships within "the Quad," — which includes Japan, Australia and India — in the face of the looming security threats and economic challenges posed by China.

But the development of a deeper and broader alignment across the Indo-Pacific that can push back against China's assertiveness seems to remain elusive, as indicated by the mixed response to Russia's invasion of Ukraine and the vagueness of a just-launched U.S. economic engagement initiative in the region.

During his three-day visit to Japan through Tuesday, Biden suggested that a firm global response to Russian President Vladimir Putin's "barbarism" in Ukraine may shape the future behavior of China, which seeks to bring Taiwan into its fold, by force if necessary.