Americans see Martin Luther King Jr. as a hero now, but that wasn't the case during his lifetime

The fact that King is now beloved and has a national holiday commemorating his birthday wasn't something that during his lifetime appeared would obviously happen. During the 1960s, King was a very divisive figure.

source https://www.cnn.com/2023/01/16/politics/martin-luther-king-jr-polling-analysis/index.html