The conservative Heartland Institute was going for shock value when it mounted a digital billboard in Chicago that combined a mug shot of the Unabomber, Ted Kaczynski, with the message: "I still believe in Global Warming. Do you?" (See the full image below.) After the group faced a fiercer backlash than expected, however, it promptly took down the sign and canceled plans for similar ads. Here's what you should know:

What was the point of this billboard?
The Heartland Institute was trying to be "deliberately provocative," the institute's president, Joseph Bast, said in a statement, "to turn the tables on the climate alarmists" using their own techniques. Tired of being branded as the bad guys for questioning the view that humans are causing climate change, the group planned to post a series of billboards featuring "rogues and villains" — including Kaczynski, Osama bin Laden, Fidel Castro, and Charles Manson — to point out that, when it comes to global warming, these evildoers share the view of the United Nations, mainstream media, and liberal politicians.

Is it any wonder that didn't go over well?
Perhaps not. But it wasn't just liberals who complained. Rep. Jim Sensenbrenner (R-Wis.) threatened to cancel his speech at Heartland's climate change conference later this month if the group failed to take down the sign. "We can win this debate without the name calling," his spokesperson said. In another blow, beverage giant Diageo, which gave the institute $10,000 in 2010, announced that it would no longer be contributing.

Has the institute always been so controversial?
The free-market think-tank has been making more headlines than usual recently. General Motors had been funding the group for two decades, but the automaker severed its ties in March, shortly after leaked documents exposed a plan to disseminate a new school curriculum focused on "dissuading teachers from teaching science." The documents spelled out the organization's efforts to encourage debunkers to question the scientific consensus that CO2 from the burning of fossil fuels is causing warming and shifting weather patterns.

Does the billboard have its defenders?
Yes. The "flinching" of the Left shows that Heartland succeeded in calling attention to "extensive work debunking global warming science," says Anne Sorock at Legal Insurrection. Putting out white papers only goes so far, and I'm glad the institute is "thinking creatively" about how to beat the alarmists at their own game. Huh? says Andrew Sullivan at The Daily Beast. Likening the majority of the world's scientists — and other sane people — to murderers and madmen is "an almost perfect illustration" of the Right's "refusal to acknowledge scientific reality" and its reliance on "brutalist" propaganda instead of honest, civilized debate.

Sources: Chicago Tribune, Daily Beast, Guardian, Legal Insurrection