Are Staffordshire Bull Terriers dangerous, or is it the owner's fault?

Every dog has the capacity to be aggressive, even breeds considered more gentle such as a Golden Retriever. I personally think it's more the owners that lead the dog to have terrible behavior, typically from a lack of training and obedience. Staffordshire Bull Terriers are not for novice dog owners, they required experienced dog owners who are firm and consistent. They can be great family dogs, as they are very loving, but they need early socialization. I strongly recommend that if you get one, you enroll it in puppy preschool and training so it can learn socialization and start on training it. Best of luck, I hope this helps!