Harry Potter and the Second War

What if, when Harry and Hermione traveled back in time in Prisoner of Azkaban, they had captured Peter Pettigrew and brought him to justice? With one simple act, history changes, but there is still the Second Wizarding War to be fought, and history has a great weight of inertia. What lies in store for The Boy Who Lived and his friends? AU from near the end of Ch. 21 of PoA onwards.