And he fell right into the trap, American progressives readily gobbled up the bait so they don't have to think about the real issue, they can do something. Prior to that we had Rachel Dolezal and another dizzying bit of logical head flipping. The same people who told us 'race was simply a social construct' said she could not identify as another race...because she is white.
Now, she is clearly nuts, she invented a black father, but even if he were real that race is a biological or social construct is a false dichotomy, note Science 2.0 faves Alex Berezow, Ph.D., and Michael White, Ph.D., here and here respectively.
Obviously a whole lot of medical research evaporates to the detriment of society if woo-promoting 'race is only social' types convince scientists that white people get sickle cell anemia and black people get cystic fibrosis equal to everyone else.
Berezow and Razib Khan sum it up nicely in USA Today, writing
Rather, genetics compels us to view race and ethnicity as part of a larger journey that started with our first ancestors who evolved over the course of tens of thousands of years into the riotous colors and shapes that we recognize as human.