Magnanimous or just cynical? Whatever the reasoning, big-tent politics is the name of the game on both sides of the Atlantic. Photograph: Reuters

In some ways, they could not be further apart: Obama speaks with a silver tongue, while Sarkozy can be alarmingly blunt. Obama wears shoes with regular soles. Sarkozy doesn’t.

But while observers have noted the many differences between both leaders, little has been said about the opportunities and challenges of their common political approach: reaching across the aisle, or politique de l’ouverture.

As President Sarkozy recently reminded us by appointing the late Socialist President Francois Mitterrand’s nephew to head the prestigious French ministry for cultural affairs, l’ouverture means more than making promises in a speech on election night. It has become a constant feature of postmodern politics, where independent voters are often decisive blocs.

Appointing members of the opposition paints a leader as broad-minded, reaching for the centre ground and away from old, divisive politics. More cynically, it denies the opposition talents and ideas, a tactic not foreign to Sarkozy or Obama, who co-opted his former rival Hillary Clinton rather than leaving her out in the cold, where she might well have caused trouble for him. But while l’ouverture is good politics, it may not make for good policies.

With characteristically rapid execution, Sarkozy did not wait to be elected to make his first moves across the French political aisle. In the thick of the presidential campaign, his Union pour un Mouvement Populaire (UMP) party brought on the Socialist Party’s chief economist, Patrick Besson. The UMP broadcast Besson’s defection as proof that the Socialists were losing their way and their best brains. After a low-profile stint as junior minister for economic prospective in Sarkozy’s first government, Besson has recently been upgraded to head the ministry for immigration and national identity and Sarkozy presents him as a rising political star.

Sarkozy’s big-tent approach served two purposes. One was to address his sharp-elbow, conservative image, that of the man who as interior minister called for using fire hoses to clean the “scum” of the unruly suburbs. The other was a growing threat coming from his centre-right flank led by Francois Bayrou, who as the third man in the first round of presidential elections secured an impressive 18 percent of the votes. It came as no surprise that Sarkozy’s first government included 6 ou......