"...with sovereignty the instrument that allowed it to achieve its aim--that is to say, obedience to teh laws--was the law itself; law and sovereignty were absolutely inseparable. On the contrary, with government it is a question not of imposing law on men, but of disposing things; that is to say, of employing tactics rather than laws, and even of using laws themselves as tactics--to arrange things in such a way that, through a certain number of means, such and such ends may be achieved.
"I believe we are at an important turning point here: whereas the end of sovereignty is internal to itself and possesses its own intrinsic instruments in the shape of its laws, the finality of government resides in the things it manages and in the pursuit of the perfection and intensification of the processes which it directs; and the instruments of government, instead of being laws, now come to be a range of multiform tactics. Within the perspective of government, law is not what is important: this is a frequent theme throughout the eighteenth-century texts of the Physiocrats which explains [sic] that it is not through law that the aims of government are achieved."
From his lecture on Governmentality.