No, blue nose pitbulls are not aggressive. Like all pitbulls, they have a reputation for being aggressive because they were bred as fighting dogs, but there is no evidence that they are a particularly aggressive breed.
Blue nose pitbulls are actually American pitbull terriers, not a separate breed. Although they are muscular and powerful dogs, they’re typically happy, friendly, and somewhat goofy. They’re devoted to their human family and are so good around children that they’ve earned the nickname ‘nanny dogs’.
If they are correctly trained and socialized from puppyhood, there’s no reason why they should show signs of aggression.
However, if you’re adopting a blue nose pitbull and are unsure about its history, you should be cautious until you’re sure it’ll remain calm in all situations. As a precaution, always supervise it around children and people your dog doesn’t know, who may inadvertently scare it, causing an unwanted reaction.