THE presidents of Kenya, Uganda and Tanzania took another key step towards establishing a regional common market when they launched the East African Community on Tuesday. The East African Community treaty aims to create a free trade area in East Africa and to allow freedom of movement across borders for nationals of the three countries. But with Tanzania and Uganda reluctant to expose their fragile industries to competition from abroad, the three countries have decided to negotiate the more controversial details about the removal of trade barriers at a later date. Under the treaty, the three countries will negotiate the framework of a customs union over the next four years, and will then move on to establish a common market.