U.S. Vice President Joseph Biden, center, his wife Jill Biden, right, and U.S. President Barack Obama walk towards the Oval Office after an announcement in the Rose Garden of the White House in Washington, D.C. on Oct. 21. Photographer: Mike Theiler/Pool via Bloomberg

Countless barrels of ink are spilled on the post-presidency. What will each commander in chief's legacy will be? Where will their libraries be erected? What will they do in their years after office, especially if they're young?

Far less attention is paid to what vice presidents have done or will do in their post-White House years. And yet, right now that's a question on many people's minds given that Joe Biden has decided not to run for office. Ending months of speculation over whether he would take one last crack at the top job, which has been a decades-long ambition of his, Biden said Tuesday that "unfortunately, I believe we're out of time, the time necessary to mount a winning campaign for the nomination."

We rarely ruminate much on the post-vice presidency, partly because the next step for vice presidents is often predictable: a quest to be commander-in-chief. As vice presidents have taken on more active roles in the modern era, the job has become more of a stepping stone to the Oval Office—rather than one seen merely as "the spare tire in the automobile of government," as John Nance Garner called the job.

Vice presidents, after all, can appear as partners in the president's success, viable candidates who've been painted with the stature of the office, and veterans who've had an up-close view of the role. In the post-war era, seven of the 11 vice presidents who didn't ultimately become president (in other words, leaving out Lyndon Johnson and Gerald Ford) did at least run for the top job, either in the immediate election or in later years.

Had Biden chosen to run, history would not have been on his side. It's actually extremely rare for vice presidents to be elected president immediately after they've served as No. 2. George H.W. Bush pulled off that trick in 1988, but the last time it happened before that was in 1836, when Martin van Buren was elected at the end of Andrew Jackson's presidency.

Richard Nixon, of course, served as Dwight Eisenhower's vice president, but he was not elected himself until 1968, eight years after his time as second in command. Nine more vice presidents became commander-in-chief after a president died or resigned in office; yet only four of them were later elected in their own right.

So what did the rest do once their vice presidencies came to an end? Harry Truman's vice president, Alben Barkley, sought the Democratic nomination but didn't win it; he later came out of retirement to run for and win a Senate seat in Kentucky. Spiro Agnew, who resigned after a bribery and corruption probe during Nixon's administration, became a business consultant and wrote a novel.

Dan Quayle, who declined to run in 1996 but tried in 2000, withdrew from the race and now serves as chairman of Cerberus Capital Investments. And after Walter Mondale was defeated in the landslide 1984 election, he went back to practicing law, served as ambassador to Japan, and narrowly lost a bid in 2002 for his old Senate seat.

Who knows if Biden will ever run for Senate again, write a novel or join corporate boards. Reports say he has told friends he doesn't have plans for a traditional retirement, and has mentioned options like starting a foundation or an institute at the University of Delaware.

Then on Tuesday, he offered a few more hints during his speech. Biden said that "while I will not be a candidate, I will not be silent" in his final months in office, planning to lead from the sidelines of the 2016 campaign. "I intend to speak out clearly and forcefully, to influence as much as I can where we stand as a party and where we need to go as a nation," he said.

And as he and his family continue to mourn his son, Beau Biden, who died of brain cancer in May, the elder Biden tipped his hand about another possible project. "I believe that we need a moon shot in this country to cure cancer. It's personal," he said. "I'm going to spend the next 15 months in this office pushing as hard as I can to accomplish this, because I know there are Democrats and Republicans on the Hill who share our passion, our passion to silence this deadly disease. If I could be anything, I would have wanted to have been the president that ended cancer, because it's possible."

Maybe, just maybe, Biden's post-White House years will create a post-vice presidency that doesn't involve the Oval Office but that the world still well remembers, rather than forgets.

Read also:

How time ran out on Joe Biden’s presidential dream

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