I was listening to an old ASSA seminar (mp3 at link) on Environmental Economics and Government Policy and David Zetland asked a question and received an answer of:

In response to my question ("were you able to revoke policies that failed an economic cost-benefit?"), they answered "No. It's really hard to kill a policy that's in place. Most of the good we did was in preventing bad ideas from moving ahead."

This is not news. But ought this not imply that the bar should be much higher on whether a particular government program should be implemented? Given that the cost of getting it wrong is likely to be institutionalized for a very long time, it would seem to me as a matter of  "Precaution" that far fewer government programs should be implemented and those that are implemented must overwhelmingly pass a cost-benefit test. If folks wish to pursue the Precautionary Principle as it pertains to preventing bad outcomes from unknown risks, then why ought it not also be applied to the risks imposed by bad government policy? Or is the Precautionary Principle not really a legitimate principle at all, but yet another trojan horse for statism in dressed up in the disguise of science, like the Nudging Revolution in economics? And to take the risks of government a little more seriously, isn't it the case that governments are responsible for starting and executing most of the major wars in modern history, killing hundreds of millions of people in the process? If we are to take the Precautionary Principle seriously, wouldn't this require a minimalistic government just to prevent the possibility of a World War III from wreaking a kind of havoc that Climate Change alarmists could only dream about? Please do tell me what is different.