How did the ideas of social Darwinism help revive assumptions of superiority of the Anglo-Saxon race at home and abroad?

Social Darwinism used the concept of "survival of the fittest" to justify racial superiority, arguing that certain races were more evolved and therefore more fit to dominate others. This led to the resurgence of beliefs in the superiority of the Anglo-Saxon race, both domestically and internationally, as a way to justify colonial expansion and reinforce existing power structures.