ORIGINAL: Chickenboy
From the Wiki entry on the Battle of the Philippine Sea:
Spruance was heavily criticized after the battle by many officers, particularly the aviators, for his decision to fight the battle cautiously rather than exploiting his superior forces and intelligence data with a more aggressive posture. By failing to close on the enemy earlier and more forcefully, his critics argue, he squandered an opportunity to destroy the entire Japanese Mobile Fleet.
"This is what comes of placing a non-aviator in command over carriers" was the common refrain.[43] Admiral John Towers, a naval aviation pioneer and Deputy Commander-in-Chief Pacific Fleet, demanded that Spruance be relieved.[44] The request was denied by Admiral Nimitz. Moreover, Spruance was supported in his decision by Nimitz, Kelly Turner, and the top naval commander, the acerbic and highly demanding Admiral Ernest King, Chief of Naval Operations.[45]
In retrospect, it certainly is instructive to compare Spruance's caution (in particular, his suspicion of a diversionary force) with Halsey's headlong pursuit of an actual diversionary force at Leyte Gulf four months later. Halsey left the American invasion fleet weakly protected, and exposed to a nearly successful attack by Japanese heavy surface units.
So another way to read this is-if Spruance had done the needful and finished off the IJN surface fleet, then Halsey wouldn't have had to pick up his leavings and do his dirty work later off Cape Engano. [;)]
This, of course, presumes that he could have finished off the entire IJN surface fleet, when only part of it was present at The Battle of the Philippine Sea. Spruance did manage to sink 3 out of 5 fleet carriers in the action. There were also 5 battleships, 13 cruisers and numerous other ships present in the IJN fleet.
Some of the ships in the diversionary fleet that Halsey went after later were not present in the Battle of the Philippine Sea, including the
Ise, Hyuga, Oyodo, Tama, and
Isuzu, so there was no way for Spruance to destroy that part of the diversionary fleet. Would Halsey gone after just this? Given his aggressive tendencies, i would guess he would, although, again, it is speculation.
Junyo and
Ryuho which were present at the Battle of Philippine Sea, were not present at Cape Engano.
Zuikaku, Chitose, Chiyoda and
Zuiho were present at both battles.
There were 9 DDs also present at Cape Engano, but i am not sure sure which ones, or if they were present at both battles.
To think that Spruance could have destroyed the entire fleet during the battle of the Phillippine Sea is, well, not reasonable. It took planes from 11 fleet aircraft carriers much of 1 day (from launch to recovery) to take out
Yamato,
Yahagi and 4 DDs off Okinawa. This is 4 more fleet carriers than Spruance had at the Battle of the Philippine Sea (however, he did also have some light carriers).
Halsey went after a far smaller force with almost as many ships (5 fleet and 5 light carriers) as Spruance had at Philippine Sea, and (despite attacking against 1/7 the number if planes Spruance had to contend with) still didn't destroy the entire diversionary force even after pursuing for an additional 3 hours after receiving the "world wonders" message from Nimitz. Halsey finally turned back to help Kinkaid, but not soon enough to do anything. So, he accomplished neither goal - neither complete destruction of the IJN diversionary fleet, nor supporting the invasion fleet. Had he managed either goal, i think maybe he would be looked on with more favor by historians.