WASHINGTON — It is rarely a good idea to make campaign promises that put you in a box or could go very wrong, as nearly every president can attest.

Joe Biden must have skipped that chapter in the campaign how-to handbook. He’s now stuck with vows to appoint women and minorities to key positions that he could find complicated to keep.

Not only has he promised a female running-mate but also an African American woman to the Supreme Court. There’s nothing wrong with these goals, which are overdue, but problems arise when circumstances change.

The pandemic, for example. It would be smart for Biden to consider New York Gov. Andrew M. Cuomo as his running mate, if for no other reason than that Cuomo, along with NIH epidemiologist Anthony S. Fauci, are about the only names many Americans trust in this time of national crisis.

It may prove equally vexing to find a black woman for the high court given that most justices are culled from federal appellate courts. There are only five black women currently serving on U.S. appeals courts, all of whom will be over 68 this year, according to NBC News and the Federal Judicial Center. Democrats may prefer someone younger to get the nod.

Biden made this promise just days before the South Carolina Democratic primary where black voters are essential to victory. The next day, he received the golden endorsement of House Majority Whip James E. Clyburn, D-S.C., who is credited with handing the nomination to Biden. Black voters throughout the South came out in droves for ol’ Joe — and now they’re passing the collection plate.

But that promise cannot be kept until he is elected and whether he is elected may turn on how he keeps the first promise: to name a female running mate. It’s safe to say that at no other time in recent history has the person riding shotgun been so critical. Biden would be the oldest president to assume office at 78 and has begun lately to look challenged at times by his age. Thus, voters must be able to envision the vice president, whoever she might be, as the president of the United States. And even if Biden bears up well, his pick will likely be next in line, at least, for the Democrats.

If I were Sen. Kamala Harris, who appears to be on the short list, I’d drop my bid for the number two spot and make a play for the high court. She’s sat on the Senate Judiciary Committee, and has been a former prosecutor and California’s attorney general. And she is young, age 55.

Another reason Harris may want to bet her chips on the Court instead of the vice presidency: She was often sharply critical of Biden in the debates, as in the time she all but drove Biden to his knees, repenting a regrettable anti-busing position decades ago. It was an unnecessarily humiliating moment for Biden that likely struck many Americans as more unfair than righteous.

Stacey Abrams, a former Georgia representative and unsuccessful 2018 gubernatorial candidate, has also been mentioned as a possible VP. A Yale-educated lawyer, she’s a social-justice, voting-rights warrior who blames voter suppression for her loss, by 55,000 votes, to Gov. Brian Kemp. On a personal note, she had me at, “I’m not going to do class warfare; I want to be wealthy” when she said those words in a recent speech. But she’s unlikely to be widely viewed as qualified for the nation’s top office.

I’m not sure that can be said of Congresswoman Val Demings, D-Florida, a former Orlando police chief. Some say Demings will help Biden with black voters who view his 1994 crime bill as racist. But as a presence on the camera? She would be a far more convincing commander-in-chief than the current occupant.

This brings us to Minnesota Sen. Amy Klobuchar, the Minnesota “nice” candidate who brags about winning in “red districts.” Alas, she happens to be white and, perhaps more troubling to liberals, a moderate. While liberals prefer someone more progressive and others are demanding an African American woman on the ticket, such concerns should be understood as less important than winning in November. With all due respect to Charlamagne tha God’s insistence that Klobuchar would hurt black voter turnout, it is hard to believe that Klobuchar would be a net loss for the Democrats with so many red and purple states seemingly in play

The path to victory isn’t paved with progressive promises. It looks more like Main Street: a broad avenue of hope for a sane, steady future. The vast majority of Americans are ready for the middle road. Klobuchar has a cheerful outlook, a sharp mind, an impressive Senate record and a comforting, maternal vibe who could allay concerns about Biden’s age and health. If winning is the goal, she’s Biden’s best bet.

He can square the circles after he’s elected.

kathleenparker@washpost.com.

©2020, Washington Post Writers Group