Because the Bible tells us that Satan was doing the driving.
Luke 22:3 Then Satan entered Judas, called Iscariot, one of the Twelve.
John 13:27 As soon as Judas took the bread, Satan entered into him.
Did God not use the devil and Judas to do His will? Just as God hardened Pharos heart that His will would be done concerning Moses and the children of Abraham.
W.W.