Satan's access to the heavenlies will end half-way through the seven-year treaty [of the Great Tribulation period] when he and his angels are cast out of heaven by Michael, the archangel.

       When he is thrown from heaven to the earth, he will totally possess the soul of the wicked dictator who will take  over the revived Roman Empire.

            Then this man will become the Antichrist, satan possessed. At that time he will force the people to worship him as god.