The National Security Strategy put out one year after "September 11" shows that the Bush administration has more or less finalized its global strategy. The adjustment of US global strategy is meant to strengthen its dominant position in the world, and counter-terrorism and security are the top priority issues for US new global strategy. The core concern of US foreign policy has also been shifted from advocating "democracy" to safeguarding "security . The war against terrorism offers a new opportunity and driving force for the US to improve its relations with big powers including China. Although the US will continue to be on guard against China, it no longer regards China as its adversary, and engagement and cooperation with China have become the major component of US' China policy. To grasp the opportunity of strategy in the first two decades of the 21st century, China should properly handle and develop its relations with America and other big powers to create a long-term and stable peaceful international environment.