This should be a somewhat familiar theme to readers, but I recommend Sean Wilentz’ appreciation of Ulysses S Grant in the wake of conservative efforts to knock him off the $50 bill in favor of Ronald Reagan:
In reality, what fueled the personal defamation of Grant was contempt for his Reconstruction policies, which supposedly sacrificed a prostrate South, as one critic put it, “on the altar of Radicalism.” That he accomplished as much for freed slaves as he did within the constitutional limits of the presidency was remarkable. Without question, his was the most impressive record on civil rights and equality of any president from Lincoln to Lyndon B. Johnson.
Of course part of the issue here is that conservatives don’t care about civil rights. They fought it tooth and nail until 1964–65 and then suddenly in 1966 stopped supporting white supremacy and simply started taking the view that basic civil rights is all well and good but now the left is taking things too far. They don’t think slavery was a big deal and the only racism issue they recognize is the fear that someone, somewhere, is being too hard on white folks in the name of anti-racism run-amok.
So in that sense the neglect of the Grant Presidency is to be expected, unfortunate though it may be. It’s also worth pointing out that Ben Franklin and Alexander Hamilton are on our money, so non-Presidential achievement is something we’re clearly allowed to take into consideration. And his term in office aside, Grant was the commanding general who won the Civil War. That alone is a pretty serious qualification.