Just want to point out - I've taught in a few different states, one of them being very red and another overwhelmingly blue - no one I've encountered or worked with has "thought" this. There's some interesting correlations that can retroactively be made, certainly, but no one is arguing that 1+1 = racism. The papers I've read all deal with the human systems around math (as in, the people teaching it, and in continuing education, the administration around it) being accused of exclusion, biases, and harassment of different minorities. Not the math itself. As a female minority, I haven't encountered overt racism (from the education system), though obviously everyone's experiences are their own.
I also want to point out that normalizing certain behaviors and fostering specific traits *is* part of our job; they just aren't the traits that most people think of when someone says "social indoctrination." I teach educational tolerance and critical thinking - behaviors that we have universally agreed are socially required for hundreds of years. Again, I can't speak towards every teacher out there, but please don't think every educator is actively brain washing children to go against what their parents believe.