President Obama came to office promising an era of political comity, but even he has had to concede that his first 15 months in office haven't lived up to his campaign hope of transcending partisan divisions. While it takes two to tangle, we think the hyper-polarization owes more than a little to Mr. Obama's own rhetorical habits. More than any President in memory, Mr. Obama has a tendency to vilify his opponents in personal terms and assail their arguments as dishonest, illegitimate or motivated by bad faith.

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