There is not yet a theocratic kingdom proper. At this moment, Satan is still called "the god of this world / age" (2 Cor 4:4; John 12:31). 

God is sovereign of course. His sovereign rule has always been true. Jesus is sitting at His right hand, awaiting the appointed time to crush His enemies like grapes or like a footstool under His feet. Jesus was explicit however that the throne of David will not be established until after He returns in Glory, in the resurrection, in age to come. We are not yet in the resurrection. “Truly I say to you, that you who have followed Me, in the regeneration when the Son of Man will sit on His glorious throne, you also shall sit upon twelve thrones, judging the twelve tribes of Israel." (Mt 19:28) “But when the Son of Man comes in His glory, and all the angels with Him, then He will sit on His glorious throne." (Mt 25:31) - Joel Richardson