Robert Greenwald puts out a video on McCain's penchant for rage. Former senator and fellow Keating Five member Dennis DeConcini's anecdote is telling. Having witnessed one of McCain's explosions firsthand in the Senate dining room, I can personally testify that I have very rarely seen any outburst of temper more explosive and nasty. Now, I have a temper too. I'm not judging the man, whose passions are real and whose service to his country should be honored. But I'm not running to have my finger on a nuclear button and facing down Iran and Russia. Temperament in a president matters. Especially after what we've seen these past six weeks, I worry about McCain's in an international crisis.

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