Which General had the most potential to affect the direction of the war at the moment of his death? Anyone mentioning Jackson at Gettysburg better make it good or its Andersonville for you old boy! A.S.Johnson? Birdseye McPherson?
My two are Philip Kearny Jr. and Charles Ferguson Smith...
Kearny is marked for corps command at least by Lincoln at the time of his death at Chantilly. Implacably hostile to McClellan and an acquaintance of Lincoln's going back to before the Mexican-American War, he had the advantage of actually fighting in battles of 100,000s before the Civil War, fighting with the French at Solferino. He originated the idea of the corps badges that his friend Hooker expanded on. He originated his own medal, the Kearny Cross, in frustration with the failure of Congress to authorise awards for the men which inspired the Medal of Honor. He had a positive view of recruiting freedmen having formed his ideas watching Africans in French service fight in North Africa and Italy. Imagine a Chancellorsville with Kearny as a corps commander or as Hooker's no.2 ready to step in...? Or Kearny at Antietam attacking in conjunction with other corps because he's not waiting for orders from McClellan (who Kearny thought a coward at best, a traitor at worst)...?
Charles Ferguson Smith had been Grant and Sherman's teacher at West Point. Appointed to serve under Grant he was steadfastly loyal to Grant. He showed his skill whipping his raw recruit division into a force fit to perform outstandingly at Fort Donelson. Smith's experience, dignity, and unselfish character made him Grant's mainstay. Sherman spoke of him fondly too. When Grant was relieved by his enemy Halleck it was Smith who was placed in command. If he had lived he would have led his division at Shiloh (W.H.L. Wallace replaced him). A living C.F. Smith likely stays at Grant's left hand just as Sherman is at his right. If Smith lives then who knows - he might be the one marching on Atlanta...or he might be one of Sherman's wing commanders instead of Howard or Slocum. Perhaps he keeps McPherson from rising to corps command...?
These are my favourite two "the General lives" what ifs. One for the East and one for the West. What are yours?