I know -- twenty-year rule.

I'm currently reading up on Chican@ history (in order to broaden my historical understandings, and to have a point of comparison to understand my own ethnic history as an Asian American). One of the things that was noted was that restrictions against Mexican immigration in the early 20th century (1900s-1930s) were rather lax. Part of the explanation for this lax attitude was because employers wanted cheap labor; because the US government had severely curtailed Asian immigration and had strictly restricted European immigration, employers seeking cheap labor looked towards Mexico to find laborers.

Obviously, this attitude has since changed. You would have to be living under a rock to not notice the rhetoric of anti-(Mexican)-immigration by a number of Republican politicians.

So, why did this change? Does the reopening of Asian immigration in the mid-1950s/1960s have something to do with it?