What is this, Touch?

Watched football with the old man yesterday, and came to a dispiriting conclusion: No one in the NFL knows how to tackle anymore. When I was in youth football, they taught me that the way to bring someone down was to hit him hard accross the waist and legs. This way, you shift his center of gravity and undo his forward momentum. I watched two games yesterday, and everyone was trying to tackle by grabbing the ball-carrier by the shoulders. This does not work. It was frustrating to watch offenses pile up yards that should have been stopped at first contact. It isn't that the running backs or receivers are getting stronger and faster, it's that tackling isn't getting done. No wonder these guys celebrate for two minutes after knocking someone down.