Imagine a Major League Baseball stadium constructed to actually fight lung disease. Imagine engineers eschewing asbestos in every form, using only materials approved by the American Lung Association. Imagine emergency inhalers at every seat, with team officials aggressively marketing the “healthy-lung” park to conscientious fans.

Then imagine your surprise, in visiting the park, to see a huge Marlboro cigarettes ad plastered across the left field fence. Imagine another Marlboro ad behind home plate so TV viewers can’t look away. Imagine, finally, being asked to stand and sing Take Me Out To the Ball Game during the “Marlboro Cigarettes 7th Inning Stretch.”

Sounds absurd, right? Well, welcome to Nationals Park in Washington, D.C., for an inconceivable variation on this theme. With public alarm over global warming at an all-time high, team owners of the Nationals baseball team spent millions for a “healthy Earth” park, with environmental features like low-flow plumbing and energy-efficient lighting. The new park has been officially declared a “green facility” by the National Green Building Council, the first of its kind in American sports.

But visiting fans know the rest: Strike Marlboro cigarettes and substitute “ExxonMobil” and you have the astonishing reality at Nationals Park. Oil giant ExxonMobil, the biggest contributor to global warming of any company in the world, has its name splashed across the left field fence and, intermittently, behind home plate. ExxonMobil, which invests almost nothing in clean energy while gasoline goes to $4 per gallon, is the feel-good sponsor of the 7th-inning stretch, so your child can happily sing about peanuts and Cracker Jacks while the company logo sparkles on the biggest scoreboard in baseball.

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No wonder a coalition of concerned groups — ranging from faith leaders to college students to environmentalists — announced Friday it would protest outside all Nationals home games until Exxon stops its ads.

Their message to the Nationals is this: Thanks for the fluorescent bulbs, but you can’t be a “green” building if your number one underwriter is wrecking the planet. The climate crisis needs more than half measures and half loaves. It needs a full commitment from all of us, especially institutions like baseball that speak so powerfully to our children.

The comparison to cigarettes is more than symbolic, of course. Exxon has done more than any oil company to cast false doubt on the avalanche of science connecting fossil-fuel combustion to the planetary cancer of global warming. The company has spent millions funding quack “scientists” and front groups reminiscent of J.R. Reynolds in the 1960s. Even now CEO Rex Tillerson says there’s too much uncertainty over the cause of global warming to take national or international action.

What uncertainty? Right now, Allstate Insurance company will not issue new homeowners policies in coastal Maryland, Virginia and six other states because of projected sea-level rise and bigger storms. This is not politics or spin. Allstate is not a Republican corporation. It’s not a Democratic firm. It’s a private independent company with its own capital at risk and it is retreating from the U.S. East Coast because, it says, oceans are rising and extreme weather events are becoming more frequent.

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Indeed, just last month, the National Wildlife Federation released a study showing nearly two-thirds of the coastal beaches in the Chesapeake region will be lost to global-warming-induced sea level rise unless we take strong action soon. The Anacostia River, in fact, on whose bank the new Nationals Park rests, is itself a tidal river vulnerable to sea level rise. If the Greenland ice sheet melts as many scientists say is now possible, we’ll get 23-feet of Potomac-Anacostia River rise in downtown D.C.! Ironically, the playing field at Nationals Park is already several feet below sea level. So the Exxon ad in left field could itself be under water due to our continued use of the advertiser’s product!

No wonder the mass media and average citizens have been so concerned about these issues of late, with the “go green” mantra a staple of national discussion. So hats off to Lerner family, owners of the Nationals, for their pioneering greenness. Among its features, Nationals Park includes copious bike racks, its own in-house recycling facility, and easy access to the D.C. subway. On June 4th, the team asked fans to wear green clothing to a game to show their support for the environment.

Too bad those same fans had to see all the Exxon ads and sit through the Exxon “7th inning stretch.” And too bad Exxon, outside the park, continues to make a mockery of everything the Nationals try to do. In total contradiction of scientific facts, Exxon recently helped fund a campaign to encourage one million American Christians to write Congress questioning the role human beings play in driving global warming.

This, again, is the moral equivalent of denying the role cigarettes play in lung cancer. It is utterly unacceptable. The Nationals’ owners are harming their reputation, their community, and indeed our nation with their blatant association with the world’s biggest environmental abuser.

If Marlboro cigarette ads were plastered all over Nationals Park, there’d be a social uproar. We’d complain and keep our kids away and we’d demand change. It’s now time to do all the above with Exxon.

I’m a huge baseball fan and a full-on Nationals nut. But I’m also the father of an 11-year-old boy. Is my love of Major League baseball so great that I’d do the equivalent of offering my son a smoke?

What do you think, Washington Nationals?

To learn more and get involved with the campaign, visit Strike Out Exxon.