To fight climate change, start with Leonardo DiCaprio's private jet lifestyle Even though Donald Trump withdrew from the Paris climate agreement, there's plenty Congress can do.

Glenn Harlan Reynolds | Opinion columnist

So last week President Trump pulled out of the Paris climate agreement — to the extent that one can pull out of an agreement that’s not actually legally binding, anyway. This left some people upset.

But if climate change is really such a crisis, and if sacrifice on our part is needed to stop it, then why aren’t we seeing more sacrifice from people who think it’s a problem?

That’s what one person asked on Twitter: "What if climate scientists decided, as a group, to make their conferences all virtual? No more air travel. What a statement!” And what if academics in general — most of whom think climate change is a big deal — started doing the same thing to make an even bigger statement?

It would be big. And what if politicians and celebrities stopped jetting around the world — often on wasteful private jets instead of flying commercial with the hoi polloi — as a statement of the importance of fighting climate change?

And what if politicians and celebrities lived in average-sized houses, to reduce their carbon footprints? What if John Kerry, who was much put out by Trump’s action, gave up his yacht-and-mansions lifestyle?

What if, indeed? One reason why so many people don’t take climate change seriously is that the people who are constantly telling us it’s a crisis never actually act like it’s a crisis. They’re all-in for sacrifices by other people, but never seem to make much in the way of sacrifices themselves.

Well, some might say, that’s why we need laws. Even people who are deeply concerned about climate change lack the self-discipline to change their behavior. So we need discipline to be imposed, by the force of government.

Well, okay. Since some states and cities are promising to live by the Paris agreement anyway, and since Trump’s rejection of that agreement doesn’t mean that Congress is forbidden to act, I have some proposals for legislation that will take climate change seriously indeed.

First, we need to tax the “blue zones.” That is, we need to impose steep taxes on property in coastal areas that will be flooded by the sea-level increases that global warming is supposed to bring. By discouraging people from living or building there now, we’ll save ourselves from big problems in the future. Sure it’ll drive down property values, but those values should go down — they’re values for property that’s going to be flooded anyway, remember?

Second, we need to ban taxpayer-funded air travel to conferences. State legislatures could ban reimbursement for travel outside their states; Congress could require that no federal grant money be spent on air travel to conferences and similar events. A lot of academic conferences would fail, but that’s a small price to pay for saving the planet. And besides, it will encourage the development of Internet-based conference alternatives. A whole new industry might result: Green jobs!

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Third, we need to ban private jet travel. At first I thought about just taxing it heavily, but with the planet at stake, that might not be enough. It’s nice that John Travolta can have his own Boeing 707, or that Leonardo DiCaprio can jet around the world speaking against climate change, but the carbon emissions involved set a bad example that outweighs anything he might say. So no more private jets. Bigshots will just have to fly commercial like everyone else, the way they did in the 1950s. (And sorry, Leo, but massive yachts have to go, too). Politicians, too, should have to fly commercial. No more government-funded “executive jets” for them.

Fourth, we need a luxury tax on mansions. Any home more than twice the size of the average American home should be taxed at 25% of its value per year. Celebrities and the rich enjoy great powers of persuasion — but with great power comes great responsibility, and they have a great responsibility to set a good example for the rest of us on climate change!

These proposals are just the beginning, and I’m sure that enterprising members of Congress and various state legislatures can come up with more. But the important thing is to set a good example: Treat climate change like the crisis you say it is, and maybe more people will believe that it really is a crisis.

Glenn Harlan Reynolds , a University of Tennessee law professor and the author of The New School: How the Information Age Will Save American Education from Itself, is a member of USA TODAY's Board of Contributors.

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