On the post-1900 board, I just posted a comment on how Churchill and FDR were indispensable to their respective countries in 1940, although the other alternatives would certainly have been effective under different circumstances (Eden, Attlee, Wilkie, Dewey). It made me think about other leaders who were indispensable, such as Lincoln.
Lincoln is no doubt a great president, and one of my favorites (it's between him and FDR). But Lincoln's resume does pale in comparison to Seward's and Chase's, and Lincoln's lack of experience did hamper him a bit early on in his administration. Seward and Chase were the leading contenders for the Republican nomination in 1860. Would either of them had been as capable as Lincoln if they got the nomination instead? I think Chase's abrasive personality would definitely have hindered his effectiveness; I'm not sure about Seward. None of the 3 had any military experience, so they're equal in that respect (and military experience oddly enough wasn't helpful to Jefferson Davis in being an effective wartime president). What does anyone else think?