What does Revelation 12:3 mean?
John saw another sign appear in heaven. A great red dragon—the second of seven important figures mentioned in this segment of Revelation. Verse 9 identifies this dragon as the Devil and Satan.The dragon had seven heads and ten horns, and each of his heads had a diadem: a crown-like object similar to a headband. The imagery suggests that Satan holds absolute sway over political entities in the tribulation. The ten horns represent ten kings who reign for a while with the first beast mentioned in Revelation 13:1. Daniel 7:7–8, 23–24 prophesies this confederacy of ten kings. Today, as "the god of this world," Satan dominates the evil world system (2 Corinthians 4:4), but this influence will be even more potent, and more obvious, during the tribulation.
In John 12:31, Jesus called Satan "the ruler of this world." When he tempted Jesus, he offered Jesus all the kingdoms of the world if Jesus would fall down and worship him (Matthew 4:8–9). In the tribulation Satan's political power will reach its peak. He will use the two beasts of Revelation 13 to suppress millions of people.