It'd still take extraordinary effort to persuade (shame) prosecution to take action. But with some transparency, at least the torrent of evil stuff would be recorded by someone somewhere.
And how about something a bit more formal? Maybe modeled after police department citizen review board? With a staff to injest, process, and interpret stuff? Like Project Censored.
I half thought that maybe Wikileaks might do some of this. And I should have probably scouted a bit before asking for something that already exists. (I hadn't actually ever visited the site before. I've never been terribly eager to get myself added to some watch lists.)
Alas.
https://search.wikileaks.org/?q=war+crimes
Not much value add there. It really is just a fancy FTP site with a search engine. The org itself does some competent press releases, swag, and branding; that ain't nothing.
It's as much politics on the ICC side as on the USA side.
For years, the ICC had only prosecuted former warlords from African countries. Only the loosing sides, the criminals that won national power were usually ignored, as the recent Ivory Coast shows. So some African leaders protested and even removed their country from the ICC. So the court had to react, at least to show an intention even if a real prosecution is totally unrealistic. So the ICC Prosecutor — which is the former Ministry of Justice of the Gambia dictator — launched inquiries about crimes by security forces of Myanmar (Birmania), Israel, USA… It's mostly a symbolic gesture.