The longest pro-environment speech ever in a big budget Hollywood movie is probably at the end of On Deadly Ground (1994). It's ~3:30 and it's given by the lead character played by Steven Seagal.

As text

Closing scene: Speech given at the Alaska State Capitol building in Steven Seagal movie, “On Deadly Ground.”

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I’d like to start out by saying ‘thank you’ to all the brothers and sisters who have come here representing this cause.

I’ve been asked by Mr. Itaka and the Tribal Counsel to speak to you and the members of the Press about the injustice that has been brought against us by the government and big business.

How many of you out there have heard of ‘alternate engines’ – engines that can run on anything from alcohol to garbage or water; or carburetors that can get 100s of miles to the gallon, or electric or magnetic engines that can practically run forever? You haven’t heard about them because if they were come into use, they [would] put the oil companies out of business.

The concept of the combustion engine has been obsolete for over 50 years, but because of the oil cartels and corrupt government regulations, we in the rest of the world have been forced to use gasoline for over 100 years.

Big business is primarily responsible for destroying the water we drink, the air we breath, and the food we eat. They have no cure for the world they’ve destroyed. [They care] only for the money they make in the process.

How many oil spills can we endure? Millions and millions of gallons of oil are now destroying the ocean and the many forms of life they support. Among these is Plankton, which supplies 60-90% of the Earth’s oxygen, and supports the entire marine ecosystem which forms the basis of our planet’s food supply. But the plankton is dying.

I thought, ‘Well, let’s go to some remote state or country – anywhere on earth’ – but in doing a little research, I realized that these people broker toxic waste all over the world. They basically control the legislation; and in fact, they control the law. The law says no company can be fined over $25,000 a day. For companies making 10 million dollars a day by dumping lethal toxic waste into the ocean, it’s only ‘good business’ to continue doing this.

They influence the media so that they can control our minds. They have made it a crime to speak out for ourselves; and if we do so we are called ‘conspiracy nuts’ or laughed at.

We’re angry because we’re all being chemically and genetically damaged, and we don’t even realize it. And unfortunately, this will effect our children.

We go to work every day, and right under out noses we see our car and the car in front of us spewing noxious and poisonous gasses that are accumulative poisons. These poisons kill us slowly, even when we see no effect.

How many of us would have believed 20 years ago that on a certain day we wouldn’t be able to see 50 feet in front of us; that we wouldn’t be able to take a deep breath because the air would be a mass of poisonous gas; that we wouldn’t be able to drink out of our faucets; that we would have to buy water out of bottles; that the most common and God-given rights have been taken away from us; and unfortunately, the reality of our lives is so grim nobody wants to hear it.

Now I’ve been asked what we can do. I think we need a responsible body of people that can actually represent us, rather than big business. This body of people must not allow the introduction of anything into our environment that is not absolutely biodegradable or able to be chemically neutralized upon production.

And finally, as long as there is profit to be made from the polluting of our earth, companies and individuals will continue to do what they want. We have to force these companies to work safely and responsibly, and with all our best interest in mind, so that when they don’t, we can take back our resources and our hearts and our minds to do what’s right.