Most Americans' understanding of western expansion is obtained from movies set in the west starring John Wayne? Is that a fact or a rationalization? _Little House on the Prairie_ certainly romanticized the Old West and _The Waltons_ certainly romanticized the Great Depression. Now, look up any list of famous westerns and look at the plot. Even the ones starring John Wayne tow the line. If you believe that being lynched, shot, raped, starved, or otherwise terrorized by roving bands of thieves or railroad-hired thugs is romantic, well then, I stand corrected. Here's a list to get you started. Which of these romanticize the Old West?

https://www.theguardian.com/film/filmblog/2013/nov/08/top-10-movie-westerns 

Here's a valid criticism of portrayals of the Old West: they fail to show the rampant and violent racism directed at Native Americans, Chinese immigrants (who built the railroads), and the Mexicans of conquered Northern Mexico and that many cowboys were black.