While we have the OP as a fine example of my point, it might help to provide an example of your own. In developed economies, nationalization has historically occurred when a business that the public relies upon has become literally or effectively bankrupt. Can you think of an example of an inefficient nationalized industry in the UK, the EU, or the USA? And in what way has nationalization contributed to that inefficiency?

In many cases the services that have recently been privatized were never nationalized to begin with - they were public services, like garbage collection or public transport, that have no obvious market competition model to follow.

Your definition of "rent-seeking" is also incorrect. Rent-seeking behaviour is when an economic agent attempts to manipulate public policy for private gain. A government body cannot engage in this behaviour by definition, as it does not take a profit, and is not private. It can fight its corner though - seeking more funding - but then it must spend that money on things like schoolbooks or hospital beds. This is considered a horrifying waste of resources to the private sector, which knows that those funds could better be spent on yachts and hookers.