Who says they were? Those cultures have a long history of slave capturing and trading, plus ruthless and cruel—even murderous—exploitation of peoples in their occupations, trading hegemonies, and colonies! Sure, after the 20th century’s World War II, with, for example, the UK’s complete withdrawal (some call it abandonment, from the way they went about it starting in the previous century), they’ve had more convincing bragging rights about their ‘liberalism’. But that’s pretty darn recent.