But using a commercial number is absurd, as precisely this is a matter of public policy, and at most the cost of borrowing of governments (1-2% above expected inflation, i.e. 3-4% today) should be used.

The underlying argument here is that governments have no proper role, even to tackle such economy-wide, or civilisation-wide issues. This is a fundamentally ideological position, a fundamentalist one, in fact.

This is the result of the past 30 years of anti-tax, anti-government propaganda. The governement is not good for anything (except that it is used anyway as an unending source of pork and of bigbrotherish invasions of privacy and individual rights)

In the long run, we're all dead. John Maynard Keynes