President Obama called the cash-for-clunkers scheme, which ends on Monday night, “successful beyond anybody’s imagination”. He is right on at least one count – money was certainly put to work quickly. Originally slated to run from July through October or until its $1bn of funding ran out, the scheme lasted barely a month, even after funding was boosted to $3bn.

On other criteria, the programme was less successful. By failing to anticipate demand and allowing a large backlog to develop, administrators looked amateurish and initially enthusiastic dealers faced cash shortfalls. Some chose to stop taking part early to allow time for the required paperwork. Such difficulties contrast with scrapping plans in Europe and threaten to become a liability for a president advocating a government role in healthcare.