Qadhafi's mafia state

With all the focus on the end of the Qadhafi dictatorship in Libya, it is timely to also ask how Qadhafi managed to stay in power for 42 years, largely unchallenged. The Muftah blog has some interesting commentary on the 'mafia state' created by the Qadhafi family in which civic values were completely absent. Here is an extract:

Symptomatic of how it was run [the state] is an incident in 2009, in which
two of Qadhafi's sons fought each other with military tanks until one of
them forced the other to sell him his shares in a new Coca Cola plant in the
country.