is meant to express that the U.S is taking much, much longer than it should to reach an end of segregation and/or racism in general. Uses this metaphor creates a strong and obvious image of a slow rate; as well as specifically picking a horse and buggy rather than say, oh I don't know, a snail, installs this idea of old-timey ways that need improvement. The metaphor strongly impacts the reader and easily delivers the idea that the U.S is not advancing properly.
is meant to express that the U.S is taking much, much longer than it should to reach an end of segregation and/or racism in general. Uses this metaphor creates a strong and obvious image of a slow rate; as well as specifically picking a horse and buggy rather than say, oh I don't know, a snail, installs this idea of old-timey ways that need improvement. The metaphor strongly impacts the reader and easily delivers the idea that the U.S is not advancing properly.