The end does not neccessarily justify the means but if something works it was probably right.

Truth is preeminently to be tested by the practical consequences of belief.-William James

Suppose I was a cop and I was told by my superior to take a squad and apprehend a person believed to have murdered his family. Suppose I apprehended or killed the person and in doing so lost a member of the squad. Then it turns out that someone else killed the guys family but he was discovered to be a serial killer and he had murdered a half dozen other people.

If it turned out that the superior had manufactured evidence and lied to me because he didn't like the guy or he thought he was a shifty character, I would have a major problem with that even though the guy turned out to be a serial killer. On the other hand, if the evidence that he killed his family turned out to be incorrect for any number of reasons that did not include willful deception by my superior, I would be pleased to have gotten a dangerous guy off of the street. Should the evidence that sent me after the guy be examined? Sure, but it should be done by the appropriate people and it should not be a witch hunt. Scale it up or scale it down. It is all the same.

From a practical standpoint, the more culpable the criminal the less interest the public will have in how he came to be apprehended. That might not sit well with an idealist but I don't see it as being morally bankrupt.

I hope that whatever investigation that needs to be done will be done and in the end we will probably do the right thing because we are basically good. Unfortunately, some will never be satisfied with whatever is done but most will be okay with it

The way events should unfold is to attain results that will provide security for my family and my grandchildren's families. We should obtain the results in a way that will not cost us our soul and we should try to do some good for the rest of the world along the way but like Dan says it is a war against a more or less monolithic enemy that is determined to destroy us and survival is our primary goal.