Most likely, GE would have chosen someone quite similar to Welch had he not accepted the job, Mukunda says.

FORBES: Why Most Leaders (Even Thomas Jefferson) Are Dispensable

In the book, Mukunda classifies every US president from George Washington to G.

FORBES: Why Most Leaders (Even Thomas Jefferson) Are Dispensable

George W. Bush was unfiltered, Mukunda says, because he spent less than six years as governor and was boosted by family connections.

FORBES: Why Most Leaders (Even Thomas Jefferson) Are Dispensable

This article is by Gautam Mukunda, an assistant professor at Harvard Business School and author of the forthcoming Indispensable: When Leaders Really Matter (Harvard Business Review Press, September 2012).

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