Tolerance is not new. Our country was basically founded by the need for people to find religious tolerance. Did they get it? Not really, but it was a hell of a lot better than what passed for tolerance in other countries, where they let you pray to the God of your choice right before they burned you at the stake.
You can bet the Protestants, Catholics, Jews, Buddists etc. weren't mixing it up on the weekends, they weren't intermarrying, doing business with, or if they could help it, interacting at all...they just weren't killing each other because of who they were. Tolerance.
No doubt the word has evolved....otherwise it would be impossible to swallow statements like "The Dutch simply facilitated it" when discussing the subjugation of whole races into slavery.
But I don't think that being tolerant requires that anyone embrace other cultures if they don't want to...that simply defies the actual meaning of the word. All that is required is that you recognize that some people are different from yourself, whether it be in color, language, dress, custom, or worship....respect it, and leave it the fuck alone. That's it. I think Affirmative Action had its part in history, but is no longer necessary....I am completely against reparations for slavery, unless you, yourself were actually a slave.....and I don't think anybody should get a free pass to anything.