How come the Big 12 conference top teams don't play a lick of defense?

The Big 12 top team is all offense and no defense. I mean looked at OU today, Texas score a lot of points on Mizzou but they allowed to much yardages and to many points against them. Also TTU is all offense and Texas A&M stayed close to TTU until the 4th quarter, wow al offense and no defense. Will the Big 12 top teams win the BCS title with these kind of defense? I mean no defense, it's all offense.