The Algerian hostage taking underscored the rapidly escalating tensions in a region where French troops have come to the aid of the fragile government in neighboring Mali as it seeks to block the advance of militants. Here's a primer on Mali and the region:

Q What is Mali?

A Mali is a large, but very poor country in West Africa. Centuries ago, it used to be a center of culture, knowledge and wealth. The Malian town of Timbuktu is popular with tourists for its history, or at least used to be until Islamist rebels took it over.

Q Is this crisis happening because of the war in Libya?

A That's one part of it. For decades, Libyan leader Moammar Gadhafi cultivated close ties with the Tuareg, whom he used to harass his neighbors and as mercenaries. When Libyans rose up in 2011, Gadhafi deployed Tuareg fighters against his own people. But when his regime started to fall, the Tuaregs went home to Mali. The already formidable fighters were now equipped with training, weapons and, in some cases, a Gadhafi-bred hatred of the West and of their own governments. They put all of those to use in rebelling against their government. There's another really important factor that's not related to Libya. In March 2012, some mid-level officers in the Malian military staged a coup in Bamako, toppling the democratically elected government. With the capital in chaos, the Tuareg rebellion that had begun in January quickly swept across the north.

Q Is Al-Qaida in Mali?

A There are four different groups of rebels in northern Mali right now. Those Tuareg are called the Movement for the Liberation of Azawad (MNLA) and they're considered relatively secular. But not long after their independence, extremists within their own movement started to emerge. Now the MNLA has been marginalized within its own rebellion, largely replaced by two breakaway Islamist groups: Ansar Dine and the "Movement for Oneness and Jihad in West Africa" (MOJWA) Ansar Dine, the better-known of the two, has recruited Arab fighters from a group that might sound familiar: Al-Qaeda in the Islamic Maghreb. The link between Ansar Dine and Al-Qaida in the Islamic Maghreb is not totally clear. Also unclear is their link to the "central" Al-Qaida organization. But they are all cruel, imposing extreme social restrictions and barbaric punishments on, for example, a woman who served a glass of water to a man.

Q What's going to happen?

A The two big models that people talk about are Afghanistan and Cote d'Ivoire. Call them the pessimist's view and the optimist's view.

The pessimistic case is that, like Afghanistan, it could turn into a costly, open-ended conflict. The pessimists point out that Mali's north is about the same size of Afghanistan, a vast, formidable desert that the rebels know well and outsiders do not.

The optimistic view is that France has deep experience in West Africa, where it has conducted military interventions before. It did so twice in Cote d'Ivoire, right next door. France intervened in 2002, to impose peace on a civil war, and in 2011 to preempt another war by toppling the president, who had refused to leave after losing the election. It wasn't the storming of Normandy, but it wasn't a total disaster, either.

WASHINGTON POST