It is perfectly true that some roads were built with racist intent — in all cases, as far as I know, by Democrats in the usual democrat cesspool cities. Quarantining the black neighborhoods by imposing formidable barriers to cross traffic was sometimes deliberate. Of course, this tended to trap said black folks in economically blighted ghettos, which was perfectly ok with Democrat political machines in the 1950’s and 60’s.
The more common issue by far, however, was ramming urban expressways through politically powerless neighborhoods, which tended to be disproportionately minority. The suburban cowboy lobby demanded high speed expressways from green, leafy, cul-de-sac land to downtown office districts. It’s politically next to impossible to run such arterial roads through the gentry liberal neighborhoods full of doctors, lawyers, business executives and the mayor’s political donors. The poor black neighborhoods were the path of least resistance. And of course, in years to come, urban expressways blighted most of the areas through which they ran. Urban expressways probably rank close to big welfare housing projects as a way to poison an area of the city.
Sphinx told the truth.