PBS' investigative public-affairs program reminds us of things we would rather forget. Climate change is going to be the focus of a three-part dive on Tuesday.

The weekly mini-series focuses on climate change denialism as it was practiced and paid for by the fossil fuel industry. It's a history that's more depressing than enlightening, because nothing has been done about the crisis we've been aware of for at least four decades.

The signs of our dawning comprehension and alarm are well known, among them the climatologist James Hansen's testimony to Congress in 1988, the Kyoto and Paris agreements, and the documentary An Inconvenient Truth. The response thatFrontline meticulously charts was a disciplined, coordinated campaign of obfuscation that began in industry and was embraced by conservative political groups.

There is a lot of talking heads on television and op-eds and advertorials in prominent publications that do not deny global warming but portray it as the night terrors of attention-mongering eggheads. Lobbying groups paid for by Big Oil apply pressure on politicians when it looks as if the United States might pass legislation affecting their profits.

The way in which the refusal to accept the reality of climate change prefigured the wider attacks on science was one of the lessons the show offers. The battle fought by the oil and gas industries is joined by Republican politicians when they see how climate denialism and the specter of unemployed miners and drillers are linked to their efforts to demonize President Barack Obama and radicalize conservative voters. The scientific debate is over at that point.

The larger lesson of the program is about the manipulation of emotion. The oil industry's campaign was not about convincing us on scientific grounds, but about exploiting the basic human desire to avoid taking difficult, inconvenient action. It was easy to find political cover to keep making huge profits.

Frontline tries to give this sad history some dramatic tension. When it needs a transition, or just an injection of feeling, the program throws in a bunch of disasters.

The other is more frustrating. Lobbyists, media consultants, researchers and politicians who were involved in questioning climate change testify to their actions and then offer varying degrees of apology.

Some viewers notice that middle-aged white men are in a position to have second thoughts.

While the foot soldiers offer their mea culpas, the program quietly notes the people and organizations who declined to appear or comment. Exxon Mobil said in a statement that it had done as much as anyone to shape the understanding of climate science.

The Power of Big Oil ends in a rush because of the environmental rollbacks enacted by President Donald Trump and the energy crunch the Biden administration now faces because of Russia's war in Ukraine. The final note is a sad one, as a professor whose work helped the growth of fracks and extended the life of the fossil-fuel industry wonders what kind of hell his children will have. It's doubtful that they will have much sympathy if they watch.