Lai Seng Sin / Reuters

KUALA LUMPUR—During tonight’s Democratic debate, three septuagenarian challengers will vie for the chance to take on a septuagenarian president. Or, as the 94-year-old prime minister of Malaysia might call them: whippersnappers.

It’s not unusual for kings or dictators to reign until they fall victim to Father Time. The politburos of China, Vietnam, and the former Soviet Union have generally been gerontocracies. Until the rise of Crown Prince Mohammed bin Salman, every few decades Saudi Arabia saw a transition from an “old guard” to an only-slightly less aged “young guard”. But examples of oldsters winning office in a democracy are more difficult to come by.

Mahathir Mohamad—“Dr. M.,” as he is often called here—first became Malaysia’s prime minister in 1981, and held power, unchallenged, for more than two decades, before voluntarily retiring at age 78. He enjoyed his golden years as many pensioners do: indulging in conspiracy theories, tossing out “grandpa, please” displays of casual bigotry, and carping about how the upstarts were mucking things up at the office. Then, in 2018, he sent shock waves through the nation by reentering politics to unseat the party he himself had led. In American terms: It was as if Ronald Reagan had lived on for a few decades after his presidency, and then won a new term—as a Democrat. Like a Gipper redux, Mahathir’s ideas and language can seem trapped in the 1980s. But that hasn’t seemed to hurt him yet. Although he ran as a transitional figure, he shows no signs of stepping down—and he’s so popular that even the opposition has reportedly urged him to serve out a full five-year term.

What lessons can the actual 2020 Democratic challengers learn from the world’s oldest elected leader?

Lesson One: Follow an incumbent whose failures would make anyone look good

Najib Razak, Mahathir’s immediate predecessor, first got in trouble in a rather macabre way: A Mongolian model, translator, and mistress of Najib’s top aide was allegedly blackmailing her lover for a share of the kickbacks he’d received from the purchase of two French submarines; she was murdered, and her body was disposed of using high explosives. A few years later, another scandal became public. This one featured 12,000 pieces of jewelry, 500 handbags, Britney Spears popping out of a birthday cake, a Hollywood blockbuster about corrupt Wall Street con-artistry—it even involved Goldman Sachs.

The nation’s sovereign-wealth fund 1MDB (1 Malaysia Development Berhad), the country’s rainy-day account, was essentially robbed to pay for yachts, luxury jets, impressionist paintings, and an Oscar statue won by Marlon Brando. In the end, it cost taxpayers $4.5 billion. That was what brought Dr. M. out of retirement and made him a hero to voters, many of whom hadn’t even been born the last time he held office: taking on a billionaire leader who was monumentally corrupt, contemptuous of clean governance, and surrounded by family and cronies better suited for the court of Louis XVI.

Lesson Two: Take care of mind and body

“His mind is still as sharp as ever,” Ghazzali Khalid, a Kuala Lumpur businessman and former diplomat who has known Mahathir for decades, told me. “He’s constantly trying to learn new things.” (Others have noted his interest in finance, theology, even shipbuilding.) “He tries to exercise the brain, just like the body, to prevent atrophy.”

A medical doctor by training, Mahathir has always taken a disciplined approach to physical fitness. Throughout his life, associates and friends told me, he has shunned alcohol and tobacco. In a nation that celebrates foodie culture with sinfully delicious coconut-milk rendang and nasi lemak, his dining habits are studiously ascetic. A few weeks ago, he posted a video of himself on a more than 6-mile bicycle ride.

“He’s a bit of a superman,” Sophie Lemiere, a political scientist at the Center for Southeast Asian Studies at Kyoto University who followed him throughout his most recent campaign, told me. “Despite some health problems, he keeps himself in remarkably good condition.” After two coronary-bypass surgeries, Mahathir still starts his workday early in the morning, and doesn’t finish until late at night. His top aide is said to have difficulty keeping pace with him, and he’s a younger lad: just 81.

On this score, American contenders seem to need little instruction. Joe Biden has challenged Donald Trump to a push-up contest, and it’s hard to imagine him losing. In a viral video from March, Elizabeth Warren outsprinted a reporter much her junior while dashing for a train at New York Penn Station—then gave an interview about economic policy without so much as a pause to catch her breath. And Bernie Sanders has essentially invented an Olympic sport: aerobic arm-waving.

Lesson Three: Make sure there’s no viable successor

Once you’re in power, you’ve got to make sure you can hold on to it. Mahathir mobilized a movement by allying with the unlikeliest of partners: Anwar Ibrahim, a man his government had convicted 20 years earlier on a charge of sodomy. (It’s illegal in Malaysia—a relic of British colonialism.) Anwar had once been the prime minister’s handpicked political heir, but the pair fell out in 1998. The next year, Anwar began a five-year prison sentence. He eventually reassumed leadership of the opposition, but in 2015 he found himself again imprisoned on sodomy charges. Anwar—by the time of his release, already 70 himself—then joined his old tormenter to bring down the far-more-scandal-ravaged Najib.

Dr. M.’s advanced age was supposed to guarantee Anwar’s speedy succession; after all, how long could a nonagenarian be expected to last? But Mahathir shows few signs of leaving the stage, and his closest aides are reportedly trying hard to kick Anwar to the curb. The effort took a hit, however, when a putative replacement heir was himself accused of sodomy—with a videotape to back up the charges.

When asked why they support Mahathir so strongly, many Malaysians I asked responded with a question of their own: Who else is there?

Lesson Four: It’s the issues, stupid

To the extent that Mahathir’s age is a factor in people’s minds, it may even play to his advantage. “Perhaps it has to do with Asian culture,” James Chin, a Malaysia scholar at the University of Tasmania, told me. “Age and experience are deeply respected.” This difference between Asian and Western values—whether or not such a broad generalization is indeed valid—is precisely the contrast that the prime minister has championed throughout his career. And the issues confronting Malaysia certainly deserve a steady hand at the wheel: recovery of public trust after 1MDB, questions on how to deal with a rising China, and—perhaps most important—the long-term challenges of a multiethnic, multi-religious society.

During his earlier stint in office, Dr. M. released “Vision 2020”—a plan to transform Malaysia from a society in which the bumiputra (ethnic Malays) were granted special privileges, but other communities (such as ethnic Chinese and Indians) enjoyed a disproportionate share of the economic and educational benefits. The plan made sense: Offer a big, bold agenda—and place its implementation safely three decades in the future. When he unrolled Vision 2020 back in 1991, he assumed that the thorny question of how to implement it would fall into somebody else’s lap. Perhaps the greatest challenge for Mahathir 2.0 is how to fulfill the promises made by Mahathir 1.0.

Malaysians are divided about the economy, the rise of China, Vision 2020, and everything else. These questions seem more important than how many years their prime minister has been on the planet. “His challenge isn’t that he’s old,” said Lemiere, who watched voters interact with him over the course of half a year. “It’s that he’s old-fashioned.”

In the U.S. presidential election, the incumbent and his three top challengers are, combined, half a century older than the nation itself. Will that matter? Should it? Malaysian citizens have plenty of legitimate reasons, quite apart from age, to either adore or detest Mahathir. Will the American people be willing to support a, um, mature candidate? One way or another, they probably will. Maybe give them credit for having a bit of maturity themselves.

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