The indefatigable enthusiasm of Bobi Wine, the Ugandan reggae artist and politician, is something to behold. The man oozes charisma and positivity. An avatar of hope, one feels anything is possible with him around.

Wine, who mounted a spirited challenge to de facto dictator Yoweri Museveni in the landlocked East African country’s 2021 election, makes the new National Geographic documentary “Bobi Wine: The People’s President” irresistible. Museveni, who provides a textbook example of authoritarianism, makes it depressing.

Either way, the film directed by Moses Bwayo and Christopher Sharp is riveting, if overlong and lacking in crucial context. More about that last part later.

电影开始于酒,矩形的大富豪了ording artist (his song “Kiwani” was featured on the soundtrack for the 2016 Disney movie “Queen of Katwe,” which starred David Oyelowo and Lupita Nyong’o) deciding to run for parliament. Uganda is a poverty-stricken country, and he truly seems to care for the downtrodden.

There are many energetic scenes in the film that show Wine captivating crowds of thousands, and he has a really cool campaign superpower: As a reggae artist, he wraps his campaign messages in a series of rap songs. Later, during the start of the COVID-19 pandemic, he releases a song promoting good hygiene and mask wearing.

He also has a powerhouse of a wife, Barbie Kyagulanyi, a whip-smart philanthropist who provides a moral compass.

Wine becomes a member of parliament, and then becomes a threat. He is a leading opposition voice to Museveni’s bid to undo the presidential age limit of 75 in the Ugandan constitution. That bill gets pushed through, effectively making Museveni, who came to power in 1986, president for life.

That spurs Wine to challenge Museveni for the presidency, setting the stage for the crux of the documentary, a battle of souls that sees Wine arrested more than once and many to die at the hands of the military during riots.

About the context part: Why is there such a large percentage of the population in poverty, and what are Wine’s specific policies? He wants to make life better, clearly, but how? The documentary does not say.

And how does the history of Uganda inform this moment? Not mentioned in the documentary is that Uganda was for some 70 years a part of the British Empire (that’s right: For the first decade of Queen Elizabeth II’s reign, she was also Queen of Uganda, an official title).

Since independence, there have been civil wars and a succession of brutal dictators, most famously Idi Amin (1971-79), who, incredibly, is not mentioned in the film. Nor is it mentioned how Museveni came to power and how specifically his rule has affected the country.

But the message is clear: Museveni is bad. Wine is good.

Aside from its scintillating title character, “Bobi Wine: The People’s President” is valuable because it stands as a clarion call against authoritarianism. The consensus is that more than half the people in the world live under some sort of authoritarian rule. And many functioning democracies, including our own, are showing signs of a potential slide toward authoritarianism.

This is the battle of our times, and as Wine shows us, we have to be all-in.

Reach G. Allen Johnson:ajohnson@sfchronicle.com