In November19, 2011,with the US. and Russia join the 6th East Asia Summit as formal members, the East Asia Summit will enter a critical period of development. As the result of new changes in regional economic, politic and security situation,adjustment of the US. and Russia's strategy adjustment, the admission of US. and Russia to the EAS will initiate complex regional effects, not only will affect East Asia cooperation process and regional security situation directly, but also will influence China's rising and future regional governance in East Asia. <<