At first glance, there is a great deal of convergence between what Chinese President Xi Jinping wanted and what U.S. President Barack Obama sought at their summit last week in California. Dig a little deeper, however, and the differences were every bit as important as those similarities.

While both men wish to put the U.S.-China relationship on a stable path, there is great difference in the way that each seeks to accomplish that important objective. How they reconcile that divergence will have a profound impact on East Asian relations in general, and the U.S.-China relationship in particular.

As they seek that common ground, Japan must not feel threatened. Positive relations between Washington and Beijing do not come at Tokyo's expense.