IF YESTERDAY'S major Supreme Court ruling on affirmative action were a Hollywood movie, it would be "Back to the Future Part II."

Less than a year after the high court rolled back a key section of the 1965 Voting Rights Act, the backward-looking Supremes took a bite out of affirmative action by ruling that states can end racial preferences in public university admissions - if that's what a majority of the state's voters want.

The justices' 6-2 ruling, in a case seeking to block a 2006 Michigan state referendum in which voters there banned public universities from using race to give college-admission preference, was also a win for seven other states with similar laws on the books - and it may lead to a wave of new state initiatives against affirmative action.

"Today's opinion could spark a new series of battles over affirmative action," Adam Winkler, constitutional law professor at UCLA and author of the book Gunfight on Second Amendment battles, told the Daily News by email. He said opponents of affirmative action will likely now be "emboldened" to push for state-level bans not just in college admissions but public contracting and hiring.

What does it all mean? Let's break it down:

Q: Did the Supreme Court ban affirmative action yesterday?

A: No. To the contrary, the justices ruled in a 2003 case that colleges can give racial preference to minorities in admissions, as a way of redressing many years of past discrimination. However, ruling that colleges can - as a matter of policy - impose affirmative action does not mean that they are required to use the controversial practice. So the issue at hand was whether voters can force their states to end race-based public college admissions. The majority of the Roberts Court said yesterday that they can - even though the 2003 ruling that allows affirmative action still stands.

Q: What was behind the ruling?

A: The decision turned on this basic issue: Is affirmative action a constitutionally guaranteed right for minorities, or is it a political question, based on the majority rule of the voters? Writing for the majority, Justice Anthony Kennedy called racial preference a matter for the electorate to decide. "This case is not about how the debate about racial preferences should be resolved. It is about who may resolve it," he said.

That brought a blistering rebuke from Justice Sonia Sotomayor, who took her colleagues to task for eroding minority rights on voting last year and now on affirmative action. She wrote: "As members of the judiciary tasked with intervening to carry out the guarantee of equal protection, we ought not sit back and wish away, rather than confront, the racial inequality that exists in our society."

Q: What's next?

A: Expect a broader push to copy or even expand the laws now on the books in eight states (New Hampshire is the closest to here) that ban racial preferences in public college admission. Some surveys have suggested that public support for affirmative action is slipping, although this year the Pew Research Center said 63 percent of Americans still believe affirmative efforts to increase minority college enrollment are "a good thing."

Q: How much does it matter?

A: A lot. Black and Latino enrollment at public colleges in the states that have banned affirmative action has dropped, sometimes dramatically. At the University of California at Berkeley, for example, the black enrollment rate had been the same as the state population (9 percent) before a 1998 ban, but now it's just 2 percent.

Q: What can aggrieved black and Latino students do?

A: Well, a 2013 study found the Roberts Court has been friendlier to business than any time since World War II . . . so maybe they should incorporate.