Three years after President Barack Obama vowed to shift his focus toward Asia in response to China's growing power, the advisers who set that policy in motion are gone. So is their expertise.

Instead of the Treasury secretary who had studied Mandarin as a college student in Beijing and was seen by a Politburo member as a family friend, Obama has a budget expert heading the department. While the previous secretary of state stressed the need for an Asia pivot, the nation's top diplomat now has focused on a quest for Middle East peace. And the U.S. ambassador in Beijing has said he's "no real expert on China."

As a result, former policy makers in both parties say, the U.S. is reacting to events rather than shaping them in the face of an increasingly assertive China.