George W. Bush's presidency raises two causes for concern in Sino-US relations. The first is the new President's commitment to build the National Missile Defence System. The second is the extent to which his administration will provide Taiwan with sophisticated weaponry, particularly a theatre missile defence system.
Mr Bush's Secretary of State Colin Powell has spelt out with clarity the incoming administration's view on China. He has said that China will be regarded neither as a foe nor a partner, but as 'a competitor, a potential regional rival but also a trading partner'. This is in contrast to the Clinton administration's view of China as a strategic partner.
The indications are that the Bush administration will view Japan as its main partner in Asia, leading to fears in Beijing of a Washington-Tokyo axis to contain China.
The policies of an incoming president are often tempered by the realities of office, and there is as yet no reason to suppose that Sino-US relations will deteriorate with the new administration. But clearly there is potential for friction.
An immediate cause for concern not only in Beijing but in other parts of the world, including among US allies in Europe, is Mr Bush's desire to build a nuclear missile defence system. Provided the technology can be developed, such a system would shoot down incoming missiles before they reach the United States.
The reason such a defence system sends shivers through the rest of the world is that it would give the US the kind of military superiority that no nation has ever enjoyed. With a missile defence shield, the US would not only be able to destroy potential adversaries with its nuclear arsenal but also defend itself from retaliation. Peace in the nuclear age has been maintained through Mutually Assured Destruction, by which nuclear nations left themselves open to retaliation as a guarantee that they would not use nuclear weapons. A missile defence shield would destroy this balance.
US-Taiwan relations have tended to be the rock on which relations between Beijing and Washington founder. While the Bush administration has said it will stick to the one-China policy, it has also said that it will provide for its defence needs. Beijing worries that these needs might include a theatre missile defence system which the US has said it will deploy to protect its troops and allies in east Asia.
It would help stability in the region if Washington and Beijing were to hold an early dialogue on these potential obstacles to good relations - and reach an agreement.