It is hoped that Mr Obama will understand that his capacity to mediate, let alone impose solutions on the warring sides, is inversely proportional to his current levels of popularity. But as he tries and loses popularity in the process, he will likely find that reconciling the irreconcilable is an exercise in futility.

The president needs to realise that little can be done about dynamics that are largely endogenous to the region. Much can still be achieved by containing radicalism, which will run its course eventually but only after incurring a resounding defeat. Until then, any step he takes to engage in dialogue and mediation will be seen as a sign of weakness and only further embolden America's enemies.

The Bush administration was repeatedly criticised for the arrogance of its policies - sometimes deservedly. But in a newly-humble White House, President Obama will do well to recognise how much better it is to seek limited but realistic goals than to pursue a chimera.