Is this just a case of the victor is the one who writes history?

Basically, yes. Also you do not want to glorify people who fought on the wrong side.

Also in US culture heroism is much more of a thing than in other countries like Germany and Japan. It has to do with where the society lays on the "individualism vs. collectivism". The US is a very individual country. Focus is on the achievement of the individual "dishwasher to millionaire story". All DC and Marvel Comics. It's just better material for heroic stories. Germany isn't in the position and not willing to promote heros, while the US makes a hero out of anyone who does something that's has to do with anything that's slightly more than a boring 9to5 job.