Never can a president have taken office with heavier expectations than Barack Obama did four years ago. War-weary, recession-hit, divided America heard the soaring rhetoric of the first black president's inauguration speech, forgot the folksie homilies of George W., momentarily suspended cynicism and dared to believe.

In January 2009 Obama promised to "responsibly leave" Iraq, "forge a hard-earned peace in Afghanistan" and defeat terrorists. He pledged to "harness the sun, winds and soil to fuel cars and run factories". He committed to huge infrastructure stimulus and the creation of new jobs. He promised healthcare reform and to tighten regulation of the markets. He proclaimed an "end to the petty grievances, false promises, recriminations and worn-out dogmas that have strangled our politics".

As is clear from the recent fiscal cliff-hanger, this has been his biggest failure. The same old divisions have if anything got worse, hindering everything from budget negotiations to "Obamacare" and gun control, a subject that has so coloured his first term. It's not entirely his fault. It appears the Republicans' only real policy is to stymie the President's agenda.

Now, in the 18 months before America starts obsessing about "2016" he has a chance to fulfil the promise of his rhetoric: leave Afghanistan, close Guantanamo, control guns, halt the spread of drones, give the poor better health coverage and lead the West out of recession. It is a time to be bold. Obama has the mandate, and so much less to lose this time round.

He is an inspirational, decent, clever man. Can he grasp the nettle and become a great president?

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