Sports and politics do not mix, it is often said. But that myth is having a rough summer and may have to be benched in favor of a harsher, more realistic image of the interaction between games and governing.

Take Britain's amazing snatch of the 2012 Summer Olympics from the grasp of France, Russia, the United States and other nations in early July. As new details of that secret vote in Singapore emerge, it becomes clear that major-league global politics provided London with its narrow margin of victory.

The well-prepared, systematic French bid to persuade delegates of the International Olympic Committee to award the Games to Paris after Beijing hosts them in 2008 was thwarted by a politically motivated last-minute swing of Central European countries, according to diplomats involved in monitoring the nation-by-nation secret ballot.

More on European sporting disunity in a moment. But political feelings also bubble behind the nasty transatlantic spat that is developing over Lance Armstrong's dominance of the Tour de France bicycle race, which the American won for a record seventh time in July.

Governments are staying out of the controversy sparked by reports in L'Equipe, France's leading sports newspaper, that a French laboratory recently tested a frozen urine sample originally given by Armstrong for the 1999 Tour and determined that it contained the banned substance EPO. Armstrong, a cancer survivor, vehemently denies that he ever used steroids.

But bitter disputes between Washington and Paris over the Iraq war and other foreign policy differences wend their surreptitious way through l'affaire Armstrong and help escalate it into a burgeoning test of popular wills. Behind the hard positions taken on each side of the Atlantic over a bicycle race there are lingering, across-the-board suspicions about motivation and credibility at the national level.

"This is a replay of Iraq," an avid French sports fan who coincidentally occupies a senior government post said to me in Paris last week. "Even when American lies are exposed, you expect the rest of the world to pretend nothing has happened. Why would Armstrong be an exception in a sport where doping at the highest level is so common?"

The French argument, as developed by this lone, unofficial spokesman, rests on the premise that American science has helped Armstrong develop ways to keep constantly ahead of current drug-testing methods. It seemed easier for him to accept that theory of American scientific superiority than to admit that French racers have fallen prey to the globalization of a once-proud national sporting championship.

Armstrong says it is all an ambush by "slimy" journalists that should be disregarded. He also raised questions whether someone named "Jean Francois so-and-so" could conduct an impartial test. His comments are likely to be "unhelpful," as diplomats say, in calming national passions.

More consequential are the European political tensions that contributed in Singapore to the defeat of France's heavily favored Olympic bid. It counted that Prime Minister Tony Blair spent two full days in the Asian city lobbying swing delegations while his European political nemesis, French President Jacques Chirac, spent only a few hours there.

But the French electorate's May 29 rejection of the European Union's draft constitution emerges as a more important factor in an informed reconstruction of events. In the French referendum campaign, opponents warned that the draft constitution would deluge the country with "Polish plumbers" and other job-stealers from the 10 members the union admitted in 2004.

The French non was widely interpreted as a hostile reaction to that expansion, which was not put to a popular vote. And it came after Chirac had publicly derided Poland and other Central European countries for supporting the United States on Iraq.

"When it came down to a choice between London and Paris, why would the Poles and the others do France a favor after that?" asks one European who was in Singapore. Politics worked in France's favor in swinging blocs from Africa, Asia and Latin America to Paris. But the European defections were fatal on a ballot decided by four votes.

Von Clausewitz described war as "policy by other means." In today's more compact and connected world, the immense rewards -- and scrutiny -- that come to world-class athletes turn sports into politics by other means. Truly sorry about that, sports fans.

jimhoagland@washpost.com