That literally never happened.
https://en.wikipedia.org/wiki/Haditha_massacre?wprov=sfla1
> By June 17, 2008, six defendants had their cases dropped and a seventh was found not guilty.[5] The only one of the eight charged to face punishment was Staff Sergeant Frank Wuterich. On October 3, 2007, the Article 32 hearing investigating officer recommended that charges of murder be dropped and Wuterich be tried for negligent homicide in the deaths of two women and five children.[6] Further charges of assault and manslaughter were ultimately dropped. Wuterich pled guilty to the only remaining charge, one count of negligent dereliction of duty, and was convicted on January 24, 2012.[7][8]
...
Labeling 300+ million people as "the good guys" grouping then by nation (I assume with "Americans" you mean US American citizen and not, for example, Mexicans?) but then trying to detach a nation from its politics is wild and the notion of "they are the good guys even when they do terrible things" is some weird circular or contradicting argument (depending on how I've wants to play that).