At this rate, the US presidential election of 2012 promises to be a titanic struggle between a failed incumbent and an unelectable challenger. With the election bearing down – less than two years to go – Barack Obama hit the campaign trail last week, ostensibly talking about the budget but in reality market-testing his anti-Republican message. Republicans have been slower off the mark and will need to get a move on, but the delay is understandable. They have so many weak candidates to choose from.