8-23-08, 1:08 pm

Just three days after a pulling a billboard ad produced by the Union of Concerned Scientists (UCS) from the Minneapolis airport for being 'scary' and 'anti-McCain,' the media company, Clear Channel Communications, removed a second anti-nuclear weapons billboard from the Denver International Airport that called on Democratic presidential candidate Barack Obama to re-think US nuclear weapons policy.

Earlier in the week, Clear Channel, under pressure from Northwest Airlines, the official airline of the Republican National Convention, removed a billboard by UCS from the Minneapolis airport that called on the Republican presidential candidate to reconsider US nuclear weapons policy.

After the ad had been up five days, Northwest Airlines, which has a major hub in Minneapolis, the site of the upcoming Republican National Convention, told Clear Channel that it thought the ad was 'scary' and 'anti-McCain,' and that it wanted it removed from its concourses at the airport.

UCS says the ad space was purchased specifically for the Denver and Minneapolis airports in order to reach convention-goers at both the Democratic and Republican national conventions. Both ads addressed each candidate by name in the respective convention locations.

While Northwest Airlines seems to have had a clear political motivation to pressure Clear Channel to remove the ad, no similar complaints were filed at the Denver airport, according to a press release from UCS.

Denver International Airport officials approved the ad and told one industry periodical this week that 'no one has complained' and that they did not see taking the ad down as their 'first response.'

Clear Channel agreed with Northwest Airlines assessment of the Minneapolis ad and pulled it. So far it is unclear whether Clear Channel views the Denver ad as 'anti-Obama.' Lisbeth Gronlund, a physicist and co-director of UCS's Global Security Program denied the ads were partisan and insisted they were aimed at raising public awareness of a serious issue. 'The Cold War ended nearly 20 years ago,' she said in a statement, 'but the United States and Russia still have many thousands of nuclear weapons, and each keeps more than a thousand on hair-trigger alert, ready to launch within a matter of minutes.'

Nuclear weapons, not billboards, are scary, said Gronlund. 'We need a public debate about US nuclear weapons policy, and that's why we developed these ads.' The billboards are a part of a larger UCS media campaign that includes smaller versions in bars and restaurants around both major parties' convention sites. The group also bought Web ads on Minnesota and Colorado political blog sites.

For more information, go to .