Thank you for such a thought provoking analysis, as well as so many of the responses to your post.
No one has considered the historical context of your attitude toward racism. Britain banned the slave trade in 1807. America had to fight a Civil War 53 years later to finally end the practice, but maintained legal, institutional oppression of blacks for another hundred years.
Your attitude toward racism as a Brit is over two hundred years removed for the instituition in England, completely different from that of a American born in the South prior to 1970.
Tying to understand a small segment of our population due to their perceived lack of dignity is no different than arguing that extremist Muslims or Neo-Nazis will transform with better economic possibilities. People raised in dogmatic teachings who choose the path of hatred will never change their attitudes.
Kei makes the point that only a very small percentage of Trump supporters are under 30. The vast majority of people under 30 (even among conservatives) have learned more tolerance (toward gays, minorities, women) in spite of their current economic situation. The passing of the last generation to grow up with segregation is going to have a profound effect on race relations in this country.
If anything, their passing will allow more people to unite in finding solutions for the economic and environmental challenges facing this country.