There is a salacious rumor in American politics which has it that Christians must prefer a theocracy to any other system of government -- and are trying to institute one here in the U. S.

No less a Reformed personage than John Calvin expressed a preference for a form of government not very disimilar to what our Founders set up.

[I]f you compare the forms of government among themselves apart from the circumstances, it is not easy to distinguish which one of them excels in usefulness, for they contend on such equal terms. The fall from kingdom to tyranny is easy; but it is not much more difficult to fall from the rule of the best men to the faction of a few; yet it is easiest of all to fall from popular rule to sedition. For if the three forms of government which the philosophers discuss be considered in themselves, I will not deny that aristocracy, or a system compounded of aristocracy and democracy, far excels all others: not indeed of itself, but because it is very rare for kings so to control themselves that their will never disagrees with what is just and right; or for them to have been endowed with such great keenness and prudence, that each knows how much is enough. Therefore, men’s fault or failing causes it to be safer and more bearable for a number to exercise government, so that they may help one another, teach and admonish one another; and, if one asserts himself unfairly, there may be a number of censors and masters to restrain his willfulness. This has already been proved by experience, and confirmed also by the authority of the Lord himself, when he established an aristocracy bordering on popular government among the Israelites, keeping them under that as the best form, until he exhibited an image of the Messiah in David. Calvin, Institutes of the Christian Religion, Bk. 4, Ch. 20, sec. 8.

For a Christian there can be no theocratic government which is not a theocratic monarchy. And that theocratic monarchy must have Jesus Christ as its king.