If you think mortgage derivative assets were toxic, take a look at this factoid from the CBO (Congressional Budget Office) on financing new nuclear plants using federal loan guarantees:
CBO considers the risk of default on such a loan guarantee to be very high-well above 50 percent. The key factor accounting for this risk is that we expect that the plant would be uneconomic to operate because of its high construction costs, relative to other electricity generation sources.
The current program, according to Daniel Weiss at Grist, will make the government responsible for 80% of a defaulted loan. With an $8 billion per plant price tag and 50% default rate, the program could stick taxpayers with billions in debt. As Weiss explains, Obama tripled the previous (2005) nuclear loan guarantee program which more than triples the risk to the American people:
Tripling of the loan guarantees is also dubious political strategy because it provides huge subsidies for nuclear power without securing the support of pro-nuclear senators for comprehensive, bipartisan global warming pollution reduction legislation...During this time of trillion dollar deficits, this is a very imprudent use of taxpayers’ money.