US companies must think that dawn is finally breaking over their operations in the Middle Kingdom. At last, US Commerce Secretary Ron Brown looks certain to end a ban on aid for exports during his seven-day meander around China. If it goes ahead, the move will level a playing field that has been unfairly tilted against US companies since China opened its doors to foreign investors in 1978. It will also clear the way for the new no-human-rights-attached MFN relationship go forth and prosper. This is not to demean important issues such as human rights and intellectual property protection. But it does put things in the proper perspective. Mr Brown summed it all up when he pointed out the United States would achieve more on human rights if it were commercially engaged than if it were commercially disengaged. European and Japanese companies which have been playing the aid-for-exports joker card for the last decade have reason to worry, but they do not have reason to complain. Now they will have to compete with American companies on areas such as service, quality, cost and training. The ultimate beneficiaries of all this will be Chinese companies, and through them, the Chinese economy. But while Mr Brown has been charged with sweeping the sidewalk clear of political obstructions, the ongoing negotiations over China's entry into the General Agreement on Tariffs and Trade (GATT) may foul the pavement. It is unlikely that China's Minister of Foreign Trade and Co-operation, Wu Yi, will sign away multi-billion dollar deals without bringing the GATT subject up. But, if the new maturity in the relationship between the world's largest developed and the world's largest developing economy can be maintained, that January 1 deadline for entry into the GATT successor, the World Trade Organisation, looks increasingly attainable.