That's the weakness (if you consider it weakness) of social contract theory. (politics.stackexchange.com)
Accordingly the state has entirely different moral obligations than an individual (see the SEP article on social contract theory as well as the «state» section of the article on Hegel). (politics.stackexchange.com)
This has been true in the past [when government was understood as God's ordinance], but in our day the State is generally viewed simply as an instrument of the will of the governed [as social contract theory would have it]. (firstthings.com)