What is a ‘state’? Sociologically, the state cannot be defined in terms of its ends. There is scarcely any task that some political association has not taken in hand, and there is no task that one could say has always been exclusive and peculiar to those associations which are designated as political ones: today the state, or historically, those associations which have been the predecessors of the modern state. Ultimately, one can define the modern state sociologically only in terms of the specific means peculiar to it, as to every political association, namely, the use of physical force.
‘Every state is founded on force,’ said Trotsky at Brest-Litovsk. That is indeed right. If no social institutions existed which knew the use of violence, then the concept of ‘state’ would be eliminated, and a condition would emerge that could be designated as ‘anarchy,’ in the specific sense of this word. Of course, force is certainly not the normal or the only means of the state–nobody says that–but force is a means specific to the state. Today the relation between the state and violence is an especially intimate one. In the past, the most varied institutions–beginning with the sib–have known the use of physical force as quite normal. Today, however, we have to say that a state is a human community that (successfully) claims the monopoly of the legitimate use of physical force within a given territory. Note that ‘territory’ is one of the characteristics of the state. Specifically, at the present time, the right to use physical force is ascribed to other institutions or to individuals only to the extent to which the state permits it. The state is considered the sole source of the ‘right’ to use violence. Hence, ‘politics’ for us means striving to share power or striving to influence the distribution of power, either among states or among groups within a state.
Politics as vocation
by Max Weber
http://www.sscnet.ucla.edu/polisci/ethos/Weber-vocation.pdf
‘Politik als Beruf,’ Gesammelte Politische Schriften (Muenchen, l921), pp. 396-450. Originally a speech at Munich University, 1918, published in 1919 by Duncker & Humblodt, Munich.
From H.H. Gerth and C. Wright Mills (Translated and edited), From Max Weber: Essays in Sociology, pp. 77-128, New York : Oxford University Press, 1946.