With Barack Obama’s exit the US is losing a saint. But a sinner may make a better president | Simon Jenkins

If a good man like Barack Obama fails to deliver on his promises, is it inevitable that a bad man like Donald Trump will do worse?

Does a good man make a good president – and a bad man a bad one? Barack Obama’s leaving speech in Chicago on Tuesday night was as uplifting as his arrival speech in November 2008. It exuded optimism, moderation and generosity. He was neither triumphalist nor sectarian. Ever adept at masking cliche with rhetoric, he turned “Yes we can” to “Yes we did”.

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