This report analyzes the intensifying challenges that Sino-Soviet detente poses for American interests and policies in the Asia-Pacific. It addresses and evaluates Soviet President Gorbachev's successful efforts at making China the centerpiece of his Asian strategy. Although both Beijing and Moscow disingenuously argue that Sino-Soviet detente will not affect their relations with the U.S. this report indicates that substantial harm has already occurred to U.S. interests in Asia as a result of Soviet and Chinese rapprochement. The report examines the widening and deepening range of Sino- Soviet political and economic ties, and states that prospective cooperative military exchanges between the two Asian communist states must now be considered likely. This assessment of Sino-Soviet detente given in this report indicates that the balance of power may be shifting in Asia in ways unfavorable to the U. S. Finally, the report calls for a recognition by U.S. decision-makers that the apparent anti-Soviet coalition forged by the U.S. in Asia, consisting of the U. S., Japan, and China, has now been broken. Not only is this part of the shift in the balance of power, but Sino-Soviet detente provides the Soviet Union with a freedom it has not yet enjoyed for decades to conduct its Asia-Pacific policy. (fr)