I don't think you're an idiot ....
I do not think that ALL NFL defensive players are out to injure other players - I do think that a defensive player would love to hit the offensive player hard enough that he could either take the player out of the game, cause him to fumble or cause him to not be able to play as well as he can - there's a subtle difference AND it is a part of the game - the NFL would not be as exciting if the really hard hits were not allowed - that is why they wear helmets, to protect the head AND to protect the head of the player that hits another player with his helmet
RG3 has become a player that the defenses realize that if they can get a good clean hit on him, he might not be able to finish the game - that is a part of the game and RG3 has to realize that he's GOT TO AVOID TAKING BIG HITS
I also think that RECENTLY the refs are looking to protect RG3 because they know he's a VERY valuable commodity to the NFL
so again - I don't think the intent of the defensive player is to "injure" another player - the 'intent' is more to hit him as hard as you can
there's a difference between coaches who encourage hard hitting and coaches who are involved with plans to take out opposing players - IMO Coach Williams tried to get his players to take out other players - IF Sean Peyton and Greg Williams did not know that such a 'plan' was in effect AND then denied it even existed - they would not have taken that punishment