Joe Biden should be honest with himself and the American people.

If he runs for president, it will be because he really wants to run — not because his dying son urged him to run, as New York Times columnist Maureen Dowd reported last weekend.

And if Biden does get into the 2016 race, it will be because the vice president — a survivor of enormous personal tragedy and political setback — is better placed than anyone to separate the weak from the strong.

He knows that Hillary Clinton is vulnerable, and not just because of the separate e-mail account she set up as secretary of state. She’s afraid to do what Donald Trump is doing: telling people where he stands and finding out who stands there with him.

In this August of Democrats’ discontent, Clinton is also vulnerable on core issues that matter to primary voters. If Bernie Sanders, a 73-year-old socialist, can draw huge, adoring crowds with his talk of income inequality, imagine what a better-known political veteran could do?

That’s what the 72-year-old Biden must be thinking.

When Sanders collapses, as he inevitably will, who better than Biden to pick up the populist flag and wave it for the little guy? Biden has been doing that since his first presidential foray, way back in 1988. Today, he’s tough, tested, and loyal to President Obama, who chose him as his running mate in 2008 to bring experience to the ticket. Obama stuck with his vice president through some embarrassing gaffes. In return, Biden has had Obama’s back. The two project a fondness and respect for one another that goes well beyond political expedience.

And who is more human in his triumphs and defeats than Biden? Who is a better antidote to the guarded Clinton and the safe campaign she is trying to run, with its last-century search for the political center? Today that seems so contrived.

The press loves Biden and all his passion and excesses; it will never feel the same about Clinton, no matter how much she talks about being a grandmother.

Put all that in a package for 2016 and you have the cold political calculation that Biden is wrapping up in a warm personal story of love, death, inspiration and mission.

There’s no doubt that Biden dearly loved his son, Beau, who died of brain cancer in May at age 46. The death was tragic on many levels, since Beau and his brother, Hunter, were the survivors of a car crash that killed Biden’s first wife and daughter in 1972. When Biden was sworn in as a U.S. senator in 1973, he took his oath of office by Beau’s bedside.

They were devoted to each other. “It was almost eerie how alike were father and son,” Richard Ben Cramer wrote in his political classic “What It Takes,” the epic story of the 1988 presidential campaign. Biden dropped out after revelations that he had borrowed lines from a populist British politician and used them without credit in a speech. But “Beau was the one who made the case for staying in,” Cramer reported.

To the end, the son believed in his dad, as sons should. According to Dowd, when he realized he was dying, Beau “tried to make his father promise to run, arguing that the White House should not revert to the Clintons and that the country would be better off with Biden values.”

If Joe Biden runs against Clinton, will that be his platform? That his values are better than Clinton’s? And if he knocks her out and wins the Democratic nomination, can he beat the Republican who runs against him?

That’s the calculation Democrats must make as Biden makes his own.

 

Joan Vennochi can be reached at vennochi@globe.com. Follow her on Twitter: @Joan_Vennochi.