Heatwaves were much worse in the past in the US. It is important that climate experts honor history, rather than deny it.
Lebanon, Missouri is ground zero for the 2012 heatwave. They have seen five days over 100F this year. By contrast, during 1936 they had forty-one days over 100F. During the past decade, they have had 31 days over 100F, compared to 152 days during the 1930s. Extremely hot days were five times more common during the 1930s.
The 1950s had 58 days over 100 degrees, including the all-time record high of 113 degrees. Bottom line is that the US saw much more severe heatwaves in the past when CO2 was below 320 ppm. Not only was the duration of the heatwaves longer, but the intensity was greater. The climate was hotter in the past.
Blaming CO2 for heatwaves defies history and science, and is nothing more than superstition. The 1990s had unusually cool summers after the eruption of Mt. Pinatubo, and that gap has blinded people to the longer term record.