If you play tug-of-war with your dog, could it make the dog agressive?

I've heard that it can but have not found this to be the case with my own dogs. I play tug with both of them but I always initiate and end the game, which may make a difference.

There are a couple of opinions on playing "tug-of-war" with your dog.

Some people believe that it can make a dog agressive, and even more competitive, while others feel that it allows a dog to take out some pent up aggression.

I tend to agree with the second train of thought, and believe it allows a dog to get rid of pent up aggression.

Any comments?

I don't think that it does anything for aggression. I've generally found that dogs who aren't aggressive won't play. Dogs who like tug-of-war usually know that it's a game.