The Heartland Institute paid for this billboard that ran Friday near Chicago.
A group skeptical of mainstream climate science on Friday pulled down its billboard campaign comparing climate experts to "madmen" after complaints not only by scientists but the group's own supporters.
"We know that our billboard angered and disappointed many of Heartland’s friends and supporters, but we hope they understand what we were trying to do with this experiment," Heartland Institute Joseph Bast said in a statement. "We do not apologize for running the ad, and we will continue to experiment with ways to communicate the 'realist' message on the climate."
The Heartland Institute, a conservative-libertarian public policy think tank, on Thursday had said it would be following its first Chicago-area billboard on Friday -- showing Unabomber Ted Kaczynski -- with others showing Fidel Castro and Charles Manson.
"These rogues and villains were chosen because they made public statements about how man-made global warming is a crisis and how mankind must take immediate and drastic actions to stop it," the group said in launching the short-lived campaign.
Heartland stated it chose those subjects "because what these murderers and madmen have said differs very little from what spokespersons for the United Nations, journalists for the 'mainstream' media, and liberal politicians say about global warming."
On Friday, Bast said the billboard was always intended to be an experiment.
"And after just 24 hours the results are in: It got people’s attention," he said. This billboard was deliberately provocative, an attempt to turn the tables on the climate alarmists by using their own tactics but with the opposite message."
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