Should Napoleon have taken the puppies from the mother dogs?
When Napoleon takes the puppies from their mothers in chapter three, he claims that he is making himself "responsible" for their education. In other words, he convinces Jessie and Bluebell that he has the puppies' best interests at heart and that he will personally oversee their learning.
In chapter five, however, it becomes clear that Napoleon was lying. He did not educate the puppies at all. In fact, he trained them to become his own personal bodyguards. He then uses them to expel Snowball from the farm. Later in the novel, he also uses the puppies to execute some of the other animals who threaten his dominance.
Napoleon, therefore, should not have taken the puppies from their mothers, because he did so under false pretenses. Moreover, he uses the puppies to commit acts of violence against the other animals, thereby enabling his power to grow.