Strategic dynamics in East Asia are being transformed. This process is driven by changes in the number of weapons involved — the United States and Russia are reducing arsenals, China is increasing its weapons, and new nuclear weapon possessing states are or may soon be emerging — as well as qualitative shifts in strategic capabilities, ranging from the development of missile defense, long-range conventional strike capabilities, and increasingly mobile and survivable systems. A discussion that once focused on the US-Russia strategic relationship must now take into account other nuclear powers. One of the most important strategic relationships is between the US and China.