A few weeks ago, a former colleague I have known for more than 20 years called me a racist in a Facebook post because I did not agree with all of President Barack Obama’s policies, especially his foreign policy that consists primarily of strategic dithering. This is an educated black woman with whom I had a good working relationship for many years, until that post and that charge of racism. I chose not to respond because there was no way we were going to have a meaningful dialogue about race or much of anything else after that.