Here's my takeaway from Paul Boutin's excellent article on a connection between power lines and certain illnesses: despite tons of information, the three lead scientists on this report from the California Department of Health Services didn't find a smoking gun, and are only mostly convinced that there's a connection.
It obviously warrants even further study, but a report from a group with a more vested interest estimates that $5B spent on mitigating risks (although the health group's report doesn't define how to solve the problem) might save only 1,000 lives over 35 years. This kind of estimate boggles my mind because I start thinking about $5B put into homeless shelters, drug abuse programs, and job training (saves 500 lives a year? contributes $500M to the economy?); $5B put into AIDS research (saves 10,000 lives a year?); $5B put into airbag research; $5B put into solar-power research; and on and on.
Of course, it's all about position: like parents who want to ban certain innoculations because a very small percentage of children die or develop complications (a known fact and calculable risk but not on a per-child basis), it's all about their child. Forget the fact that stopping many useful innoculations -- not all are useful anymore, apparently -- a huge percentage of children could die or develop lifelong ailments. That happens directly: the cause and effect aren't needle + child = death. They're cough and hack + disease spread = outbreak.
Once we find a cause, however, we Americans are determined to fix it. If we could really turn the greenhouse gas debate into a cause and effect, and we're getting closer with Republicans starting to admit that we are warming the Earth, maybe that's what it takes to "fix" greenhouse emissions? A smoking gun, or at least one with wisps of steam.