October 26, 2006:
The government fears that another column of rebels are rolling towards the capital (in western Chad) from the Sudan border (in eastern Chad.) Same thing happened last April, but government troops managed to kill, capture or scatter the several hundred armed rebels that reached the capital.
The government is confident that it can halt another rebel run for the capital, mainly because it has help from France, which has stationed several warplanes at the capital airport. One of those aircraft, an Atlantique 2 naval reconnaissance aircraft, recently had a portable anti-aircraft missile fired at it in eastern Chad. The Atlantique was able to detect and avoid the missile, but such a weapon indicates that the rebels are probably being supplied by Sudan. The government has been saying this for months, but Sudan is already defying most of the world, over the government attacks on non-Arab tribes in Darfur (the government is dominated by Arab Sudanese). So it doesn't really matter that the world now knows, with a little more conviction, that the Sudanese government is trying to install a more amenable faction in the Chadian capital.
It's all about the oil money. With the oil fields now producing, gaining control of the government is now more than just stealing foreign aid and development loan money. Chad's population is divided into dozens of tribes, most of them speaking different languages. This mélange of cultures never really got along together, and it took European colonial officials to hammer together the country, now known as Chad, a century ago. But it's not really a country. It's a bunch of groups contending for the prize, the right to call itself the government of Chad, and access to whatever is in the treasury.