Seemingly, in "Harrison Bergeron," Vonnegut is critical of the idea of equality by showing what would happen if all people in a society were handicapped such that no one's capabilities could rise above those of another. The consequences, of course, are ludicrous. Intelligence, physical prowess, and beauty are not permitted. This is meant to be the opposite of Lake Woebegone, "where all the women are strong, all the men are good-looking, and all the children are above average" (Keillor). Such a society is easy to rule, since no one's intelligence or strength can question or oppose a dictator.
However, while it is easy to poke fun at this form of equality, the fact is that this is not the kind of equality that is meant to exist in the democracy of the United States. Equality of opportunity and equal treatment under the law are the forms of equality that are meant to be valued in our democracy. Some people are more intelligent than others. Some people are stronger than others. Some people are more attractive than others. We anticipate that the outcomes for people will be different, and aspire to nurture the possibilities that lie in those differences. What we intend to provide is a setting in which any child can hope to succeed with education and hard work and in which every citizen can expect to be treated equally by the government.
The problem is that Vonnegut is half correct in his satire because we actually do hobble entire groups of people in the United States. For example, there really is not any difference between subjecting a child to a homeless and hungry infancy and making someone carry an extra fifty pounds while someone yells in his or her ear all the time. We choose to decline to hire people of a particular race or ethnic group. We incarcerate people who have the metaphorical equivalent of a sack of bird shot around their necks. We call it race.
So, for me, Vonnegut's little story is half a failure and half a success. Equality is not the same as equal opportunity, and it is important that a reader understands this important distinction. But there is no doubt that in the United States and other democracies, too, I'm sure, we really do subject a significant part of our citizenry to crippling forces, and this provides a permanent underclass that we can then "rule."