Good Morning in America Vietnam

Underscoring Washington's diplomatic balancing act, Gates is also due to meet Vietnamese leaders during his visit to the capital, as the country has sought US support in territorial disputes with China.

Given the prospects of an intensifying rivalry with China on the high seas, US officials say more military dialogue is crucial to defusing potential crises.

"We hope that we can work with the Chinese to put in place a framework for this military security relationship that will be able to endure friction and turbulence that is inevitable when you have a relationship of the complexity and scope of the US-China bilateral relationship," said a senior defense official, who spoke on condition of anonymity.

But he added: "We don't think we're there yet."