Kamala Harris was the safest, most experienced and most tested choice Biden could make

A man shaped by the U.S. Senate, Biden was comfortable with a legislator who had shined during difficult hearings related to President Trump’s malfeasance.

An emotive person who values personal ties, Biden chose a running mate who was close to his dear departed son Beau, from the days when Harris and the younger Biden were state attorneys general.

A White politician often referred to as “working class Joe,” Biden understood how important Black voters had been in paving his way to the nomination by giving him a sweeping victory in the South Carolina primary.

A rising movement for racial justice in the wake of the killing of George Floyd certainly made Harris’s nomination more likely. But her moderation, her long political résumé and, paradoxically, her vigorous campaigning as a Biden foe for the nomination were decisive. If she was, at moments, very tough on Biden on matters related to race, she was even tougher in everything she said about Trump.

Biden prides himself on not bearing grudges, and nothing could prove that more than picking Harris. And he knows that a vice-presidential nominee must be a fearless and ferocious prosecutor of the case against the other party and its nominee.

That was precisely the role Harris auditioned for during her presidential campaign. She will now play it from the second spot rather than the first. “Don’t worry, Mr. President, I’ll see you at your trial,” Harris said in a Twitter exchange with Trump after she ended her presidential quest. She was talking about the impeachment trial, but the jury she will now address consists of the entire American electorate.

And Harris was helped rather than hurt by leaks that some in Biden’s world regarded her as “too ambitious.” The notion of anyone in politics attacking someone else for excessive ambition is absurd on its face. Who else but ambitious people seek the presidency? But the charge carried a heavy load of sexism that turned the defense of Harris into a cause. By picking her, Biden would ratify his embrace of women’s aspirations.

Although Republicans will scour Harris’s record as a prosecutor for cases in which she was overzealous — a charge she has confronted from some civil libertarians and racial justice advocates — this argument will come with ill grace from a president who keeps tweeting the words “LAW AND ORDER.” And Harris’s past toughness on crime will complicate the very campaign Republicans want to run.

Where other nominees had sought to balance their tickets ideologically — Jimmy Carter with the more liberal Walter Mondale, Ronald Reagan with the more moderate George H.W. Bush — Biden occupies the very nearly exact center of opinion in his party: He is a moderate liberal with potential appeal to many White, blue-collar voters who defected to Trump in 2016.

Biden did not want to go too far left and endanger his ability to pull in moderates, independents and Republicans exhausted with Trump. Yet he also needs the enthusiasm of progressives, and particularly of younger voters who often don’t make it to the ballot box.

Biden’s bottom line in this decision was that there was at least as much potential for risk as for gain in any selection he made. As someone whose record has been picked over for more than a year, Harris minimized the downside risk Biden was taking.

Harris will certainly not mobilize progressives as, for example, Sen. Elizabeth Warren (D-Mass.) or former Georgia gubernatorial candidate Stacey Abrams would have. Yet the daughter of Jamaican and Indian immigrants is a breakthrough figure in American politics. Harris’s ascendancy to the vice presidency would be another milestone on the United States’ long road to full inclusion of all its citizens.

If Biden wins, he would assume the presidency at the age of 78. He thus had an obligation greater than that of any nominee in our nation’s history to pick someone whom voters could see from the outset as a plausible president.

Whatever Harris’s critics say about her, whatever attacks Trump and the Republicans hurl her way, the depth of her background makes her instantly plausible to occupy the Oval Office. That’s why she was on Biden’s list from the beginning, and it’s why she landed on top at the end.

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