Abstract: This paper points out that there is a functional incoordination of U.S. foreign policy-making mechanism, that is, a limitation of its high-end’s processing capacity, according to the principle of the limited growth of computer central processing unit and its cache. The functional incoordination embodies the U.S. President's high monopoly of foreign policy making. The U.S. President often makes some decision-making mistakes due to containments and interferences from parties resulting in the decline of American soft power. Of course, the bug of the current U.S. foreign policy-making mechanism high-end causes no serious problems while coping with the general crisis. But any low-level error from the high-end of U.S. foreign policy making mechanism will lead to deep damages to U.S. interests while playing game with great powers.

Key words: top level of diplomatic decision-making mechanism , CPU , U.S. president