The third likely element in the U.S. China relationship is therefore discord and conflict. Produced by divergent objectives that outweight common or overlapping interests, and that raise the possibility of using various kinds of pressure. Diplomatic, economic, or military to force the other side to accommodate. This kind of antagonistic relationship would differ significantly from the competitive relationships I've already discussed. A competitive relationship is not necessarily a zero s game. Since the competition may create benefits for all those actors involved, although, again, to different degrees. In contrast, an antagonistic relationship is highly likely to be a zero sum game, in which one side wins while the other sides loses. Or even worse. A negative sum game, in which both sides lose, although again possibly different degrees. China and the United States are no strangers to an antagonistic relationship, having experienced several such episodes since the establishment of the People's Republic in 1949. The most enduring cause of confrontation has been the Taiwan issue. With American interest in a peaceful future for the island conflicting with China's insistence that it retains the right to use force to achieve unification. Since the mid 1980s, however, economic and human rights have been additional sources of contention. And there's the possibility that additional issues such as climate change and economic issues may join the list if the disputes over these issues escalate. As with cooperation however, we need to understand that the relationships produced by divergent interests are not all alike, but can take different forms. There can, in other words, be different degrees of antagonism, even in an antagonistic relationship. The least serious is simple disagreement, a situation in which China and the United States have divergent interest, that they openly acknowledge but do not lead to confrontational behavior, and therefore may not disrupt the broader relationship. This pattern of behavior is frequently described by the Chinese as reserving differences, and by Americans as agreeing to disagree. The open statement of these disagreements may be irritating to the party being criticized, and they contribute to the mistrust between them, but probably will not inflict significant damage. To the broader relationship. But, the countries can also take a more confrontational approach to their differences involving the threat or application of diplomatic or economic sanctions. China has not just criticized the United States for selling arms to Taiwan, although it regularly does so. What it regards is the most objectionable form of American intervention in what it sees as a domestic issue. But at as periodically restricted military to military relations with the United States in retaliation for those sales. And for some time after the Tiananmen crisis of 1989, the United States imposed a series of sanctions on China. Because of its concerns about human rights, including halting most types of aid, and terminating the sale of military technology, also by threatening to remove China's most favorite nation status, unless its human rights record improved. Such steps may obviously lead to a tit for tat pattern, of escalatory retaliation. And may therefore do far more damage to a relationship, than simple statements of disagreement, however bluntly stated. Now the most dangerous and severe form of antagonistic relationship in international affairs, of course, is the use or threat of military force. In the case of the U.S. China relationship, the most frequently discussed danger. Would be one of two developments in the Taiwan Strait that could lead in that direction. A unilateral declaration of independence by Taiwan that China, sought to reverse through military means. Or the unilateral use of force by China to compel Taiwan to accept unification. In either scenario, the United States would have to decide whether or not to use its own force or the threat of force to uphold its residual commitments to Taiwan's security. If it decided to do so, then the risk of military conflict between the United States and China would be extremely high. A second scenario less frequently discussed would involve the Korean Peninsula. The most worrying possibility here would be, if the collapse of the North Korean regime was followed by a competitive intervention by outside powers to promote or protect their interest. If, for example, South Korea were to cross the DMZ in this situation. To be countered by Chinese forces crossing the the Yellow River. Or, if China were to intervene in the north, without a prior agreement with the U.S. and South Korea, their chances of conflict among any of those parties would be significant. Other confrontational scenarios are also conceivable. These might include a crisis over territorial disputes in the South China Sea or the East China Sea, involving China and an American ally. Or an incident between American and Chinese military forces similar to the EP3 incident of 2001. That's the incident I referred to in which two military aircraft, one Chinese and one American collided. leaving, leading to the loss of Chinese aircraft and the Chinese and the death of the Chinese pilot. Now the possibility that either of these scenarios would escalate to the point that involved actual armed conflict, between Chinese and American military forces is quite low. But cannot be entirely ruled out of additional concern is the fact that the mechanisms for managing these confrontational scenarios are poorly developed. There's little evidence that the various security dialogs have discussed what the two countries would do if any of these situations emerged. And particular China and the U.S. to the best of my knowledge have so far not be able to discuss what their governments would do, in the event of the collapse of the North Korean regime. Making it impossible to rule out the dangerous possibility of a competitive intervention that I just described. Nor do there appear to have been serious discussions, of how to manage another crisis in the Taiwan Straight. Although theres a hot line between the two capitols, there is little confidence that the top leaders of the two countries, would be able to use this channel effectively to manage a crisis. Thus far the possibility of confrontation between China and the U.S. have been reduced. More by the clarification of each other's so-called red lines than by the development of mechanisms, that can defuse a situation in which those red lines have been crossed. The former clarification of red lines is helpful. But, it cannot be an effective substitute for communication in the actual event of a crisis.