do you mean end the war so many years earlier that she would never be discovered in hiding
do you mean covertly enter occupied europe and begin evacuating civilians
do you mean entering the war in europe after d-day and pushing toward the Bergen-Belsen complex of death camps to liberate them months earlier, as well as providing the kind of necessary medical and dietary care that the inmates there would have required to survive even after liberation, something which was not initially understood and resulted in deaths at that very camp after liberation as a result of lack of experience with human beings starved for months or years on end
because Captain Confederacy couldn't even save the Confederacy, which is why it ceased to exist literally 80 years before Anne Frank died, which doesn't exactly speak volumes for his competency and tends to suggest you're a fantasist relying on your feelings and intuition instead of reality, which you apparently find unpleasant