Their work must be judged, not on the idealism and excitement they generate, but on the impact their programs and projects have on the lives they intend to affect.

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He said Mr Cameron should attend "if he possibly can" because "that would send exactly the right message that, 20 years on, we are turning youthful idealism into real leadership and tangible action at governmental and global level".

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His idealism and his legislative accomplishments will live on and another generation will be inspired by his life's works, but for the foreseeable future there will be no one like Ted Kennedy in the Senate or on the national stage.

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On Monday, MIT president L Rafael Reif praised the "brilliant creativity and idealism" of Mr Swartz, 26, who had been an early developer of the Reddit community.

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We have long moved past the stage of pure idealism and are increasingly engaging all sectors of society and government in order to make a difference on the ground.

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These are all relatively modest measures. (We centrists always try to balance idealism with realism.) Unfortunately, the larger opportunities for broad tax reform or a grand bargain on long-term deficits and debt are unlikely to come until after the election -- and there's no rational reason to expect that the hyperpartisan politics will end then.

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