SPIEGEL ONLINE: The military played a key role in the overthrow of the government in Egypt. Why is it different in Libya?

Mattes: The different role of the Libyan military reflects its different social structures. Libya, together with Yemen and Jordan, is among the nations in which tribes have played a central social and political role for centuries. In Libya, which is largely covered by deserts, the importance of tribes is largely due to the Bedouin way of life, which is based on livestock farming and the caravan trade and was dominant into the 20th century. Their survival hinged on tribal solidarity.

SPIEGEL ONLINE: How does this tribal structure affect Libyan politics?

Mattes: Moammar Gadhafi's assumption of power in 1969 resulted in members of the Gadhafi tribe (the "Qadhadhifa") and the allied Maqarha and Warfalla tribes taking over all key positions in the security arena, that is, in the armed forces, police and intelligence service, thereby guaranteeing their control. For this reason, it was never to be expected, in the event of open political opposition questioning the dominance of the three tribes, that the members of the tribes would renounce their own tribes and defect to the opposition. This sort of situation has only materialized now, because the Warfalla tribe was opposed to the Gadhafi's tribe's harsh treatment of the opposition and therefore distanced itself from the Gadhafi tribe. The Warfalla tribe can afford to change course, because it's a powerful tribe. Smaller tribes are less likely to have this choice.

SPIEGEL ONLINE: It seems as if a large number of different interest groups were coming together in Libya. How large is the actual influence of the individual tribes?

Mattes: There about 140 tribes and influential large families in Libya. According to Libyan historian Faraj A. Najm, however, only 30 have political influence.

SPIEGEL ONLINE: Did Gadhafi's takeover in the late 1960s affect the equilibrium among the tribes in any way?

Mattes: In Tripolitania, which is in northwestern Libya, the Warfalla tribe, in addition to the Wana Farsha and Tarhunis tribes, traditionally plays a central role. The small and otherwise insignificant Gadhafi tribe, which is allied with the Warfalla tribe and whose territory borders the Surt region in the east, took on a politically central and dominant role when Gadhafi came to power, a position it has been able to maintain since then by entering into tribal alliances.

SPIEGEL ONLINE: Do the tribes alone have all the say? Or are there other factors?

Mattes: In addition to the traditional tribes, the clans or large families living in Tripoli and the handful of other large coastal cities, like Benghazi, Misurata and Zwara, have been and continue to be politically influential. During the Sanusi monarchy prior to 1969, prime ministers and many cabinet ministers were recruited from these tribes, a development that continued to a lesser extent after 1969.

SPIEGEL ONLINE: The tribes now appear to be turning away from Gadhafi. How has he managed in the past to balance the interests of the individual groups?

Mattes: Since 1969, Gadhafi took a carrot-and-stick approach with the tribes. In other words, tribes that were loyal to the revolutionary regime could expect material privileges, whereas tribes which voiced opposition were punished. This principle of obedience reproduced itself in the tribes themselves: In return for absolute loyalty from tribe and family members, tribal leaders and family elders provided the leaders with material benefits and social security. These benefits included the provision of jobs or projects under the government development plans.

At the political level, Gadhafi established a committee in 1994 that was to guarantee the involvement of tribal leaders in the political decision-making process. This committee met with Gadhafi regularly, most recently on Feb. 21, to discuss a solution to the current crisis.

Gadhafi's Carrots and Sticks

SPIEGEL ONLINE: That's the carrot? What about the stick?

Mattes: It was always clear that tribal opposition was rigorously persecuted. A member of Gadhafi's tribe, for example, paid for his opposition to the Chad intervention in 1985 with his life. In 1993, an uprising by a part of the Warfalla tribe was brutally halted. The so-called code of honor, approved by the parliament in March 1997 as a result of the Warfalla incident, meant that tribes and families could be collectively punished through the withdrawal of government services, should members of the tribe get involved in opposition activities.

SPIEGEL ONLINE: Is there a historic explanation for the origins of the unrest?

Mattes: The unrest was centered in al-Baida in the country's northeast, the city where, in the 19th century, Muhammad al-Sanusi, the ancestor of the Sanusi monarchy from 1951 to 1969, founded his first religious brotherhood center. The spirit of this Sanusi order, which was considered conservative and had spread throughout the entire Cyrenaica region since the end of the 19th century, is still alive and well today and has repeatedly led to tensions with Gadhafi's modern Islam policies. This is part of the reason why Libya's Islamist movement has especially strong ties in Cyrenaica and why many al-Qaida fighters are from the region.

Starting in al-Baida, the unrest spread to the cities of Darna and Tobruk to the east, and to Benghazi in the west, and led to the proclamation of the so-called "Islamic Emirate of Barqa." Most of the movement's activists are members of the Abu Llail tribes.

SPIEGEL ONLINE: The city of Ras al-Hanouf, as an oil shipment port, could still play an important role in the protests. Who is in charge there?

Mattes: The oil shipment cities in the Gulf of Surt are in the region settled by the Zuwaya tribe, which is one of the major Libyan tribes and has frequently been represented in the government until now, by Abdulqasim Zwai as justice minister, for example. The oil terminals are still under government control. But on Feb. 20, Sheikh Faraj al-Zwai, the leader of the Zuwaya tribe, exerted pressure on the government and threatened to interrupt oil exports if the use of violence didn't stop.