So why The Big D, the not The D? Why can't metro Detroit, despite its love affair with cars, sprawl, and freeways [[the very first was built in Detroit) follow Dallas - or Cleveland, Phoenix, St. Louis, Portland, Denver, Minneapolis, Salt Lake City, Seattle, Charlotte, etc - and make light rail a reality?
...dunno... top of mind?

we're lacking several billion dollars in local and regional taxpayer buy- in? None of those places are home to the largest poorest city in the country? none of those places have deeply entrenched fears and animosity regarding race? none of those cities are the most segregated racially and socioeconomically in the country? None of those cities had their core city completely emptied of population, capital, and tax base?