Who Is the God of This World?

In this Transfiguration episode, we look at 2 Corinthians 3:12-4:6, where Paul says, "In their case the god of this world has blinded the minds of the unbelievers, to keep them from seeing the light of the gospel of the glory of Christ, who is the image of God." Who is "the god of this world" and how does he blind minds of unbelievers to the Gospel?