The nature of power of game

The phrase is a quote from the book "American Political Fictions: War on Errorism in Contemporary Culture" by Mark Greif.
The statement "In the power of the game, there is no weapon called morality" means that in a game where power is the ultimate goal, morality is not a factor that can be used to achieve that goal. In other words, the player can do whatever they want to win, regardless of whether it is considered moral or not.