Here's a look at why there's been quick action in one country, and not in the other.
The simple answer lies in the vastly different challenges faced by intervention forces. Northern Mali is home to al-Qaida-linked militants who are stocking weapons and possess stores of Russian-made arms from former Malian army bases as well as from the arsenal of toppled Libyan leader Moammar Gadhafi. The local and foreign jihadists there are digging in and training forces in preparation for jihad and to repel an invasion. Central African Republic, by contrast, is dealing with home-grown rebels who are far less organized and have much less sophisticated weapons.
The numbers of troops being sent to Central African Republic are relatively small - Republic of Congo, Cameroon and Gabon are each sending about 120 soldiers. The rebels stopped their advances toward the capital on Dec. 29, perhaps at least in part because of the presence of the foreign troops who have threatened to counterattack if the rebels move closer to Bangui, the capital. In Mali, it will take far more than the 3,000 African troops initially proposed for a military operation to be successful in ousting the militants, analysts say.
The military objectives are also a stark contrast. In Central African Republic, neighboring nations have a mandate to help stabilize the region between rebel-held towns and the part of the country that is under government control. The intervention force will fire back if fired upon, but so far are not being asked to retake the towns already in rebel hands.
The mission in Mali that foreign forces are slowly gearing up for is far more ambitious. It involves trying to take back a piece of land larger than Texas or France where militants are imposing strict Islamic law, or Shariah. Making things even more complicated there: A military coup last year that created chaos and enabled the rebels to more easily take territory has left the country with a weak federal government and the country's military with a broken command-and-control structure, and with its leaders reluctant to give real power to the civilians.
"In Mali you have a very undefined mission. What does it mean to retake the country and give it back to government forces that were not able to hold it in the first place?" noted Jennifer Cooke, director of the Africa program at the Washington-based Center for Strategic and International Studies.
Central African Republic's situation "is a more limited, defined and frankly somewhat easier mission in the military sense," she said.
Northern Mali is a scorching desert that is unfamiliar to many of the troops who would be coming from the West African regional bloc of countries known as ECOWAS. By contrast, Central African Republic's neighbors already have been pulled into past rebellions in the country.
Chadian forces helped propel President Francois Bozize into power in 2003 and they have assisted him in putting down past rebellions here.
"These forces - particularly the Chadians - have been there before," Cooke said. "They know the players, they have an interlocutor in Bozize however fragile he is. This is familiar territory to them."
The Economic Community of Central African States, or ECCAS, also already had established a peacekeeping force in Central African Republic known as MICOPAX.
"From the beginning, they knew that they needed to have troops on the ground. MICOPAX was already there, had already been deployed there. There was already a structure in place," said Thierry Vircoulon, project director for Central Africa at the International Crisis Group.
The rebels in Central African Republic are made up of four separate groups all known by their French acronyms - UFDR, CPJP, FDPC and CPSK. They are collectively known as Seleka, which means alliance in the local Sango language, but have previously fought one another. For instance, in September 2011 fighting between the CPJP and the UFDR left at least 50 people dead and more than 700 homes destroyed. Insurgent leaders say a 2007 peace accord allowing them to join the regular army wasn't fully implemented and are demanding payments to former combatants among other things. Rebel groups also feel the government has neglected their home areas in the north and particularly the northeast, said Filip Hilgert, a researcher with Belgium-based International Peace Information Service.
In northern Mali, the Islamist rebels are motivated in large part by religion. Al-Qaida fighters chant Quranic verses under the Sahara sun , displaying deep, ideological commitment. They consider north Mali as "Islamic territory" and say they will fight to the death to defend it. They also want to use the territory to expand the reach of al-Qaida-linked groups to other countries. This would seem to make other countries more motivated to intervene in Mali than in Central African Republic, but the challenges are so steep and convoluted that an intervention mission is still on the drawing board.
(Copyright 2013 by The Associated Press. All Rights Reserved.)