The crowd in Charlotte for the Democratic National Convention last week was more than a little black.The Democratic Party is, too.Roughly eight in 10 African-Americans voters have reliably cast their ballots for Democrats since 77 percent supported Harry Truman for president in 1948. Barack Obama pushed that to 95 percent in 2008 and will likely do as well this year.Helping to elect, and then re-elect, the nation's first black president has a powerful appeal. But no matter what the race of candidates the party has put up, blacks have overwhelmingly supported them.Why are black voters such committed Democrats? It's about opportunity. The signal achievement of the civil rights movement was its success in moving the government and the law onto the side of equal opportunity and toward providing it in public employment. Smaller government isn't the siren song for blacks that it is for some others.Republicans seem to miss that when they slam big government as an obstacle to individual achievement and fume about the evils of dependency they insist it encourages. Paul Ryan, the Republican vice presidential candidate, absolutely missed it when he waxed poetic in Tampa that "our rights come from nature and God, not government."They do ideally, but for blacks it just hasn't been that simple. Doing a long, hard, honest day's work was no path to freedom or success for a slave. Pulling yourself up by the bootstraps had little meaning for blacks in the not-so-distant past, when employers regularly wrote help-wanted ads that said "blacks need not apply."Or when the dream of home ownership was thwarted by deed restrictions like those in post-World War II Levittown that barred blacks, denying them that crucial route to economic security. Or when most of the nation's colleges were strictly off-limits if you were an American with dark skin.Until the civil rights successes of the last half-century, the law allowed such vicious, overt discrimination and protected the rights of those who practiced it. It has been a long slog from being counted in the Constitution as three-fifths of a person, to the 1857 Supreme Court ruling that blacks had "no rights which the white man was bound to respect," to the 1896 legal fiction of separate but equal, to finally -- after a lengthy series of court decisions and congressional actions on public accommodations, schools and voting rights -- to equal rights under the law.So, when conservatives rail against big government and how it enslaves an otherwise free people, it doesn't ring true for blacks. Big government is the voice of the previously disenfranchised in the corridors of power. It helps ensure that, when minorities work hard and play by the rules, those rules no longer bar them from the American dream of a better life.Democrats get that. It's why they cheered when the first lady, Michelle Obama, said the president "believes that when you've worked hard and done well and walked through that doorway of opportunity, you do not slam it shut behind you. No, you reach back and you give other folks the same chances that helped you succeed."A lot of what the federal government does has outstripped voters' willingness to pay. Programs such as Medicare and Medicaid have to be compassionately reformed to ensure their survival. And cutbacks in the military and public employment -- avenues of opportunity historically more open to blacks than the private sector -- are inevitable. But most blacks don't want government eviscerated. We understand it's a force for opportunity and achievement. So do other Democrats.Alvin Bessent is a member of the Newsday editorial email@example.com.