"There are very few examples that you could point to where privatizing a public good has been successful." I suppose that depends on how a public good is defined. After all, airlines for some countries were considered to be in the national interest to the point that many were owned by their national governments - ditto for steel plants, etc.
These days, I'm not sure the issue is black and white what with quasi public/private partnerships where an infrastructure project is owned by the public but leased to an infrastructure firm, or capital is raised using bonds sold to the public.
I think it's a bit naive to think that in the hands of government, rent seeking behavior doesn't happen - it is possibly even worse with contracts developed and awarded based on political connections/favor or in building roads/infrastructure in places that neither need it or even want it in some cases. There are however good and bad ways to privatize as well. I live in Ontario and the privatization of the 407 has been highly successful (both profitable and useful for private users and performs its function admirably). I try to avoid it during rush hour because of the cost (as is encouraged) but it's quite well maintained and built. Can you provide a few examples where roads have been privatized but made public again because "rent-seeking behavior and slow decay while the current owners try to wring every last possible nickel and dime out of users before reselling the husk down the line to someone else who thinks they can squeeze a few more pennies"?