It wasn’t supposed to be like this. 

Democrats thought they had the perfect candidate to take on Sen. Scott Brown in Massachusetts, whose January 2010 capture of Ted Kennedy’s long-held seat presaged the tea party uprising in November of that year. Retaking that seat in a hard-blue state was a big Democratic priority. 

Enter Harvard law professor Elizabeth Warren. She had already become a progressive darling for her tough criticism of Wall Street. While not confirmed by the U.S. Senate, she briefly joined the Obama administration after the passage of the Dodd-Frank regulatory reform bill to organize the Consumer Financial Protection Bureau, a financial markets watchdog agency. 

And then she headed back to Massachusetts to take on Brown. 

Now, it seems, decisions she made years ago threaten not only to undermine her Senate bid, but also — ironically enough — to help put the final nail in the coffin of a much-beloved liberal policy: affirmative action. 

Last month, the Boston Herald reported that Warren was listed as a “minority” in a law school directory from 1986 to 1995. Warren explained it by claiming to be one-thirty-second Cherokee, via her great-great-grandmother. (Subsequent reports have called that part of the story into question.) Her claim led many to ask about her possible use of her “Indian” heritage to navigate through various law schools before she got to Harvard. Warren denied gaming the system, saying she merely claimed Native American heritage to meet new people and go to special lunches.

The fact that these institutions initially refused to reveal whether Warren was considered a “minority” faculty member just kept the story alive. Even more embarrassing, at least one report suggests that a different Warren ancestor may have been part of the Tennessee militia that marched Cherokees out of the state and forced them to relocate in Oklahoma (the Trail of Tears). 

But a question remains: Why did Warren perpetrate an apparent subterfuge? While many people disagree with her ideologically, few argue with her intellectual bona fides. But evidently, in her rise through the professional ranks, it wasn’t enough that she was a woman; he had to check off another box, so to speak. 

That brings us to the 2003’s Supreme Court decision in Grutter v. Bollinger, in which Justice Sandra Day O’Connor crafted a tight 5-4 decision continuing the use of race as a factor in law school admissions. O’Connor declared, “It has been 25 years since Justice Powell first approved the use of race to further an interest in the context of public higher education … We expect that 25 years from now, the use of racial preferences will no longer be necessary to further the interest approved today.”

For many conservatives, O’Connor’s decision wasn’t merely wrong, it was a near-abomination. Twenty-five years for affirmative action to sunset? What more outrageous example of judges writing law instead of interpreting it could one ask for? 

Considering the fact that O’Connor was once a state legislator, her decision was not too surprising. And she may indeed have stepped beyond where she should have as a judge. However, looking at affirmative action broadly — as both a moral and historic issue — O’Connor was making a valid (if deeply misguided) point. 

Government shouldn’t be counting by race. Yet affirmative action came about as an attempt to correct centuries of America stacking the deck against African-Americans. It was out of that background that the complicated racial-preferences structure came to be. It’s hard to completely ignore the fact that slavery, segregation and institutional racism severely undercut the economic aspirations of millions of black Americans. Affirmative action, more or less, arose as redress for that economic damage.

Yet despite affirmative action’s honorable intentions, it’s pretty damn easy to game the system. Today, not only are millions of black Americans in the middle class, many are upper-middle class — and a few are even in the top 1 percent. Should their children benefit from affirmative action? More to the point: Should a very smart white woman get bonus points as a law school hire because she checks the Native American box on her application? And should an academic institution rack up political-correctness cred for such a questionable move? 

Without a coherent answer to these questions, O’Connor’s 25-year window may shut far earlier than she imagined. Before the end of the current session next month, the Supreme Court is expected to render a decision in Fisher v. Texas assessing the use of race-based affirmative action in college admissions. If the current Supreme Court effectively ends affirmative action, Elizabeh Warren may have helped add moral support to its demise. She will be the one leading liberals down their own trail of tears. How ironic: By asserting minority status from one supposed ancestor, she may end up fulfilling the terrible goal of another. 

But regardless of the legal conclusions the court reaches, Elizabeth Warren has effectively helped undermine any moral claim affirmative action once held. It was a system designed to allow the underprivileged a place at the economic table. It wasn’t supposed to help the already-privileged who happen to be cunning enough to game the system. For decades, light-skinned black Americans “passed” as white just to survive. Now — at least in Warren’s case — white Americans try to get ahead by “passing” as minority. And while conservatives are understandably furious, minorities of all backgrounds should be even angrier at how a policy has been perverted.

Robert A. George is a New York Post editorial writer.