Joe Biden’s political life always has played out against one soundtrack; it came in 12/8 time and was written by Phil Spector, an inspiration that came from his father’s tombstone. It went this way:

To know, know, know him

Is to love, love, love him.

The song came out when Biden was a sophomore at Archmere Academy, the year before he became class president. Fourteen years later, when he was a long-shot challenger to the established Republican Sen. Caleb Boggs, his team filled his campaign headquarters with the song. That theme — Biden’s uncanny gift for being liked — carried him into office and eventually into six terms in the Senate and two as vice president.

Now, as he begins the second half of his presidential term, he has found that the song, and that attribute, have lost their magic, at least in terms of his popularity. Last week, the pivot point in his tenure, a slight majority of the country said it disapproved of his performance in the White House.

All this raises two significant, intertwined questions. How much of a president’s life is determined by his past? How much of a president’s tenure is determined by the first half of his term?

All presidents are shaped by their experience; only a handful — certainly Bill Clinton, perhaps Theodore Roosevelt, but few others — are works in progress when they enter the White House. Biden’s 44 years in Washington are an indispensable prologue to his two years in the White House. Moreover, some long-established Biden traits, visible in the Senate, have become even more vivid in the presidency:

■ He isn’t doctrinaire. On a variety of issues, his views have changed over the years — fertile fodder for commentators to debate whether he examined his positions and found them insupportable (and thus was deeply introspective); or adjusted his views as his broader perspectives changed (and thus opened himself up to “growth”); or simply switched his position for craven political advantage (and thus was a mere opportunist). You choose.

Biden, of course, is not alone in changing his views. James Madison believed the creation of the Bank of the United States was unconstitutional, only to support the Second Bank of the United States while president in an economic downturn. George H.W. Bush found he had to abandon his “read-my-lips” disavowal of new taxes as the deficit widened in 1990.

For Biden, the best example of a changed position is abortion rights. He entered the Senate ambivalent if not skeptical of abortion rights. A year later, he said the Supreme Court went “too far” in its Roe v. Wade decision. By 1982, he was supporting a constitutional amendment allowing states to enact abortion restrictions, much like the 2022 high-court decision he deplored as president.

He ran for president in 2020 as a moderate, taking pains to separate himself from two rivals on his left, Sens. Bernie Sanders of Vermont and Elizabeth Warren of Massachusetts. But as president, many of his signature proposals — student debt, taxes and spending — are close to the views of his onetime opponents, making him vulnerable to right-wing charges that he has abandoned the middle lane in American politics.

■ He is sloppy. In his 1988 presidential campaign, Biden cadged a speech from British Labor leader Neil Kinnock. The presence of secret documents near his Corvette in his Delaware garage only underlines his casual approach. And his extemporaneous remarks are unpredictable and undisciplined, often leading him into dangerous territory, a quality that may have been engaging in the Senate but is full of peril as president. (In the State of the Union Address last year, he mixed up Iran and Ukraine. No one is perfect.)

■ He is notional, not strategic. The upside: Biden wants to succeed and wants the country to flourish. (His sincerity is one of his most appealing characteristics.) The downside: He is not adept in shaping a strategy for success. It was said of the 19th-century British foreign secretary George Canning that he could not “take his tea without a stratagem.” (For Biden, promulgating broad strategy is not his cup of tea.)

— He is neither mean nor vindictive. Not being Donald Trump was Biden’s most potent attribute in the 2020 election, and it remains so. As president, he hasn’t sought to demean his rivals, punish his enemies or embarrass those, like Sen. Joe Manchin of West Virginia, who have stymied his efforts.

How much of Biden’s past is prologue?

Probably most of it. Few breeds of dog develop new tricks at 80. (Adopting the revised dog-age formula from the American Veterinary Medical Association, Biden has a canine age of 414.) But a more important question may be whether his first two years — with significant achievements, from climate and drug prices to job growth and infrastructure — are precursors to his next two years.

Early in Biden’s presidency, the conservative commentator Jonah Goldberg wrote that after the tumult of the Trump presidency, “a boring old guy in the Oval Office is very reassuring to a lot of people.” That will continue to be true.

But, to adapt the counsel of investment advisers, past performance is no guarantee of future results. History provides few guideposts. Jimmy Carter had a good first two years, gaining the Camp David accords that brought Israel and Egypt together and winning approval of important energy legislation. But the seeds of disaster for the second half of his administration were sown in the first half.

Carter gave a Notre Dame commencement address in his fourth month in office saying the United States was “now free of that inordinate fear of Communism” — only to witness the Soviet invasion of Afghanistan in 1979. He visited Shah Mohammed Reza Pahlavi in December 1978 and called Iran “an island of stability” in the Middle East — only to see his embrace of the shah lead to the seizure of American hostages in 1979. Both events contributed to his defeat by Ronald Reagan in 1980.

Then again, Reagan had a disapproval rating at this point of his presidency (53 percent) that is almost exactly Biden’s figure (51 percent). He won reelection with 49 states in 1984. When it comes to optimism, Reagan and Biden are the presidency’s two beacons. It could happen again.

Recommended For You

— David M. Shribman is the former executive editor of the Pittsburgh Post-Gazette. Follow him on Twitter at ShribmanPG.