126.96.36.199 The Need for Political Legitimacy
(This is a current page, from the Patterns of Power Edition 3 book contents. An archived copy of this page is held at https://www.patternsofpower.org/edition03/6351.htm)
Political legitimacy need not mean that people approve of a government, merely that they accept its right to govern. For a government to be effective in practice, to be able to exert power in all the dimensions of governance (6.1.3), the population has to perceive the political system as legitimate.
Social stability depends on legitimacy, as David Beetham pointed out:
“Enhanced order, stability, effectiveness – these are the typical advantages that accrue to a legitimate system of power as a result of the obligations upon subordinates that derive from its legitimacy. ‘Order’ depends upon people obeying rather than disobeying. ‘Stability’ is not mere longevity, but a system’s ability to withstand shock and failure because a solid level of support from its subordinates can be guaranteed. ‘Effectiveness’ includes the ability of the powerful to achieve their goals because of the quality of performance they can secure from those subordinate to them.” 
Conversely, a lack of legitimacy can be used by disaffected groups to justify protest, violence, terrorism or revolution. Governments that have lost their legitimacy can be overthrown, as in Algeria recently: a BBC report, Algeria’s President Bouteflika is going – but that’s not enough for protesters, noted that “It seems that the government had underestimated how unpopular it had become after years of corrupt and repressive rule”.
 David Beetham summarised the advantages of legitimacy in his book The Legitimation of Power, p.33.