It's held true for the past 5,000 years.
Prehaps you prefer "the vanquished cannot bury their mistakes". Although even the victor finds it hard to bury mistakes since the advent of live news coverage.
All nations committed war atrocities in WW2, but only the 'winner' can censor their 'facts'. My dad saw a US fighter strafe and kill a Czech farmer...it wont stop me building a P-47 if I choose to do so (he doesn't know the a/c in question, I've always imagined a P-47). One farmer isnt 6 million Jews, but still I wonder how much went on that we'll never know about.