Manning was a whistlerblower, just like Snowden, with less power and ability for flight to defend themselves.

There was no personal gain ever intended or achieved, yet great personal loss even in the best outcome. They saw something very wrong happening and had little to no way to say "hey there are some incredibly powerful forces in this country doing some very evil things".

The problem is we only treat whistleblowers like traitors legally and Manning's "trial" was a complete scam, zero media coverage allowed on purpose by the government so they could be railroaded.