The history of the modern Olympics (and of other large-scale sporting events) reveals a consistent pattern. Organizers or local politicians in the host city commission “impact studies,” which almost always promise extravagant economic benefits. Studies performed after the event, however, find no positive effect at all—let alone one approaching the initial estimates. So it isn’t surprising that a PriceWaterhouseCoopers study commissioned by the British government forecasts that the Games would add about $9.4 billion to London’s GDP between 2005 and 2016. That seems like a large number until you realize that the London metro area’s GDP is roughly $712 billion annually. If the Games’ benefits were spread evenly throughout the decade, they would increase London’s GDP level by 0.1 percent each year.
Further, that $9.4 billion benefit pales compared with the cost of hosting the Olympics. In 2002, the UK’s Department for Culture, Media and Sport estimated that the cost would be $2.8 billion. Ten years later, London’s budget for hosting the Games is $15 billion. Costs already run above that figure and are likely to rise to approximately $38 billion, according to an investigation by the TV network Sky Sports. That would easily dwarf the economic benefits that the PriceWaterhouseCoopers study predicts. Security alone will be extremely costly: more British troops will patrol London than there are currently at war in Afghanistan. And these figures don’t count many hidden and indirect costs of hosting the Olympics—most prominently, disruption to business and traffic congestion. Traffic in London is already difficult; with special lanes for Olympics-related traffic, daily commutes will become a nightmare. (London’s transportation commissioner, Peter Hendy, helpfully advises commuters to go to the pub to avoid rush hour.)
This is from the Legatum Institute in London, via City Journal (which, by the by, is one of the best publications out there today, so make sure you get them in your RSS feeds or mailbox).
As I've written, the Olympics - and other such occasions of nationalist preening - are the textbook example of "boondoggle."