There is a difference however. A government established by either mutual agreement among people, or imposed by some people on all, are all derived and justified by people themselves. Any laws and regulations can be questioned, re-evaluated, and refined by people as the needs and values of the political body change.
On the other hand, the laws and regulations in a Theocratic government are not created and set down by people themselves, but rather, are set by the God endorsed by the state. These laws and regulations cannot be questioned, re-evaluated, or refined, for to do so would be to question God, or the God of the state. This inability to question or revise leads to stagnation of the body politic, an inability to evolve and improve over time.
Can you appreciate this difference between laws created by people and those created by a specific religion's God?
Everyone can investigate if the religion is from God or not, but people have the right to take what they believe is guidance from God politically and judicially as well. For a people who are certain, who better then God to govern us?
And if the laws have been misinterpreted or misattributed to God, society can investigate it. As well, the whole religion can be put into question.
But to take the right from society to seek guidance from God in government, is insanity.