Even before launching his 2020 presidential bid, Joe Biden knelt at the altar of identity grievance. He will kneel and kneel some more through the campaign. None of it will be enough, and he is destined to be mauled by the modern left’s grievance-mongers.

The “woke” social justice movement rules today’s Democrats, and the party’s candidates are ranked for fitness on a crude, ever-shifting scale of “intersectionality,” used to determine who is most oppressed. If a candidate can claim oppression based on race, gender or sexuality, he or she can move forward. If he is deemed to have “privilege,” God help him.

Before Biden officially announced his campaign on Thursday, he said at an event in January 2019: “The bottom line is we have a lot to root out, but most of all, the systematic racism that most of us whites don’t like to acknowledge even exists.”

This was of course said at Al Sharpton’s National Action Network, because a key qualification in competing for the party’s nomination is to kiss the ring of that paragon of virtue. “We don’t even consciously acknowledge it,” Biden continued. “But it’s been built into every aspect of our system.”

Anticipating that his party would demand he account for his part in the 1991 Clarence Thomas ­Supreme Court confirmation hearings, Biden has preemptively apologized for that, too — twice.

“Anita Hill was vilified when she came forward, by a lot of my colleagues,” Biden said in September 2018, after Brett Kavanaugh’s confirmation was marred by baseless sexual assault allegations. “I wish I could have done more to prevent those questions and the way they asked them . . . What happened was she got victimized again during the process.”

Six months later, he condemned his Senate colleagues who served on the panel with him — for being white, naturally.

His problem is that Biden doesn’t understand the social justice movement that has migrated from the campus ideological fringes to the center of Democratic politics. That movement isn’t sated by apologies.

Thus his cringey apologies ­invited yet more attacks. He was hit with a barrage of accusations related to his well-known habit of thirstily hugging, caressing and embracing women in public.

Kicking off the outrage, former Nevada State Assemblywoman Lucy Flores penned a piece for New York magazine to say that she had been kissed by Biden on the back of the head. It wasn’t quite assault or harassment, she conceded, but he had briefly ­invaded her space. The horror.

The column recounted a 2014 campaign stop that Biden made on behalf of Flores and other Democrats running for state office. She said she was “mortified” when ­Biden backstage ahead of her speech “inhaled” her hair and “proceeded to plant a big slow kiss on the back of my head.”

Most of us would call the incident weird and move on. But for the social justice crowd, any awkward encounter is an unforgivable transgression and comes with the penalty of having the offending party’s reputation and career ruined.

This is the party that Biden, Democrats and the news media asked for by insisting that you must believe any woman making any accusation, no matter how ­unfounded or absurd.

Biden in response to the allegations posted a video on Twitter vowing to adhere to modern rules about “boundaries of protecting personal space.”

You almost felt bad for him. The following day, three more women accused him of misconduct. Sofie Karasek said she was 22 when she met Biden at the 2016 Academy Awards ceremony and shared a story with him about someone who had committed suicide after being sexually assaulted. Biden grabbed the back of Karasek’s head and pulled her forehead toward his.

The moment was caught on camera, and The Washington Post published it at the time, calling the image “powerful.” Karasek herself had the photo framed and placed it on a shelf but then decided to take it down after the #MeToo movement began to gather steam. Identity liberalism, thou art fickle.

Biden can’t win. There are women, African Americans, a ­Latino and at least one gay man in the 2020 Democratic field. The social justice crowd will thank ­Biden for conforming to the latest woke doctrines, then kindly ask him to step aside for a candidate more properly oppressed.

Eddie Scarry is the author of “Privileged Victims: How America’s Culture Fascists Hijacked the Country and Elevated Its Worst People,” forthcoming in September.

Twitter: @eScarry