Judges 8-9: Fire in the Thornbush

The struggle for power at any cost is not new.  During the time between when the Israelites entered the promised land and when they finally had a king, they were involved in constant wars among themselves when they were not being attacked by their enemies.  One of the most flagrant struggles for power took place between Gideon's sons after his death.  His son Abimelech conspired with the town of Shechem to become their leader.  The people from Shechem gave him money which he used to hire 'reckless adventurers' who killed all but one of the remaining seventy sons of Gideon. 

Jotham, the one son who escaped, climbed to the top of Mount Gerizim and shouted this to the citizens of Shechem.
 "One day the trees went out to anoint a king for themselves. They said to the olive tree, 'Be our king.'
"But the olive tree answered, 'Should I give up my oil, by which both gods and men are honored, to hold sway over the trees?'
 "Next, the trees said to the fig tree, 'Come and be our king.'
"But the fig tree replied, 'Should I give up my fruit, so good and sweet, to hold sway over the trees?'
"Then the trees said to the vine, 'Come and be our king.'
"But the vine answered, 'Should I give up my wine, which cheers both gods and men, to hold sway over the trees?'
"Finally all the trees said to the thornbush, 'Come and be our king.'
"The thornbush said to the trees, 'If you really want to anoint me king over you, come and take refuge in my shade; but if not, then let fire come out of the thornbush and consume the cedars of Lebanon!' - Judges 9:8-15 NIV

The people of Shechem got what they wanted, an evil king, and what they deserved.  They were eventually destroyed by that very same king and he met his own disastrous end when a woman dropped a millstone on his head and cracked his skull.

In Isaiah 5, God says that he will take away his vineyard and thornbushes will grow up in their place because when he looked for justice all he saw was bloodshed. But God also says in Isaiah 55,  that we will 'go out with joy and be led forth in peace....and instead of the thornbush the pine tree will grow'. If in the end, evil always meets its own end, why are we so quick to follow after the thornbushes when it is clear that power is all they want and at any cost?