Like it or not — and lots of people on the right and left don’t like it — the Supreme Court bumped the country into the 21st century with its affirmative action, voting rights and gay marriage decisions.

Conservatives detest the court’s moving the country toward “marriage equality” for same-sex couples and liberals condemn it for ending federal supervision of voting laws in the South and limiting racial preferences in university admissions.

Both sets of decisions are steps out of the past and into the future — but just steps, not leaps. The court is nudging the country in the right direction, not shoving it.

Conservatives (including dissenters on the court itself) are denouncing the invalidation of the Defense of Marriage Act as a huge judicial over-reach. But the court did not — Roe v. Wade style — sweepingly declare that the Constitution forbids states to ban gay marriage or requires them to recognize such marriages performed in other states.

The logic of Justice Anthony M. Kennedy’s majority opinion is that some day the court might declare same-sex marriage a matter of equal rights, but so far it has simply stopped clearly unfair discrimination in distribution of federal benefits.

For now — possibly, for years — marriage law remains a state matter. Judging by the recent flow of history, it seems inevitable that most states will someday legalize gay marriage. The court went with the flow.

Meantime, as Chief Justice John G. Roberts Jr. wrote in the voting rights case, we simply aren’t living in the Jim Crow era any longer. And, though the court’s decision on affirmative action was muddled and scattered, it’s clear that the era of racial preferences is numbered.

Clearly, racial prejudice still exists and voting restrictions passed by conservative state legislatures affect minorities more than whites — probably intentionally. But all this has to be fought with modern methods — lawsuits and intense voter registration drives — not by rules devised for the 1960s.

And it’s long since time for universities to stop giving preferences to blacks simply on the basis of the color of their skin and to shift to preferences based on family income and a record of overcoming hardship.

There’s no reason for the child of an African-American professional to get a preference over the child of a white waitress. Given high poverty rate among minorities, they’ll benefit from class-based preference — but without the stigma that racial preferences now create on many campuses.

The best way to help minorities — and poor whites, as well — is to radically improve American public education. But that’s not a problem the Supreme Court can fix. It’s done what it can.