"Defense wins championships."
At least, that was the old adage before Tom Brady, Drew Brees, Aaron Rodgers and the Manning brothers started tearing up the airspace above NFL stadiums with precision strikes and ridiculous long bombs.
Still, defense wins a lot of football games in the NFL, and teams like the Baltimore Ravens, Pittsburgh Steelers and Cincinnati Bengals have built long-term success on the idea that offensive stars come and go, but a well-built defense lives forever.
These are the top defenses heading into the 2012 NFL training camps.
For reference's sake, I've included statistical ratings from the 2011 season, but statistics don't always tell the whole story. A team that controls the ball on offense and keeps scoring to a minimum will have (statistically) a solid defense, when the actual talent on that side of the ball isn't that great.
Along the same lines, a team that has a high-octane offense will often give up more points than others. That doesn't automatically mean the defense was a complete failure.
This ranking is, by design, a subjective assessment based on hours of film study over the course of the 2011 season and this current offseason. Enjoy the list and take note of the comments on each slide as much as the rankings themselves.