NEW YORK - The chief of CNN who tried to modernize the network as it fell behind the Fox News Channel in ratings has told his staff he's quitting. <br>
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Walter Isaacson -- the former Time magazine executive -- is leaving to become head of the Aspen Institute, described as a global forum for leveraging the power of leaders to improve the human condition. <br>
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He guided CNN through September eleventh coverage only two months after being appointed to the job, and helped establish new prime-time shows with Connie Chung and Aaron Brown. <br>
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But a year ago, the feisty Fox News Channel eclipsed CNN in the ratings with its blend of news and political talk, and CNN hasn't recovered the lead.
