Moreover, nearly half of Americans (47%) and somewhat fewer Chinese (37%) express little or no concern about the problem." A 47-nation poll by Pew Global Attitudes conducted in 2007, found, "Substantial majorities 25 of 37 countries say global warming is a 'very serious' problem." There are differences between the opinion of scientists and that of the general public. A 2009 poll, in the US by Pew Research Center found "[w]hile 84% of scientists say the earth is getting warmer because of human activity such as burning fossil fuels, just 49% of the public agrees". A 2010 poll in the UK for the BBC showed "Climate scepticism on the rise". Robert Watson found this "very disappointing" and said "We need the public to understand that climate change is serious so they will change their habits and help us move towards a low carbon economy." A 2012 Canadian poll, found that 32% of Canadians said they believe climate change is happening because of human activity, while 54% said they believe it's because of human activity and partially due to natural climate variation. 9% believe climate change is occurring due to natural climate variation, and only 2% said they don't believe climate change is occurring at all. Many of the critics of the consensus view on global warming have disagreed, in whole or part, with the scientific consensus regarding other issues, particularly those relating to environmental risks, such as ozone depletion, DDT, and passive smoking. Chris Mooney, author of "The Republican War on Science", has argued that the appearance of overlapping groups of skeptical scientists, commentators and think tanks in seemingly unrelated controversies results from an organized attempt to replace scientific analysis with political ideology. Mooney says that the promotion of doubt regarding issues that are politically, but not scientifically, controversial became increasingly prevalent under the George W. Bush administration, which, he says, regularly distorted and/or suppressed scientific research to further its own political aims. This is also the subject of a 2004 book by environmental lawyer Robert F. Kennedy, Jr. titled "Crimes Against Nature: How George W. Bush and Corporate Pals are Plundering the Country and Hijacking Our Democracy" (). Another book on this topic is "The Assault on Reason" by former Vice President of the United States Al Gore. Earlier instances of this trend are also covered in the book "The Heat Is On" by Ross Gelbspan. Some critics of the scientific consensus on global warming have argued that these issues should not be linked and that reference to them constitutes an unjustified ad hominem attack.