Ok, concession time.

After having thoroughly reviewed the situation with books, maps and online, and via a chat with Jambo, I concede that the Italian campaign should have never occurred. Why? Because there were better options.

If you launch a cross-Mediterranean amphibious attack from Algeria into Marseilles simultaneous, or even better - 24 hours after Normandy, then there are 4 things that could happen, all of them good for the Allies, and preferable to events such as Monte Cassino and the whole of the boot:

1.) If Kesserling hooks North and West to meet the Southern France invasion (and I'm almost certain Hitler would have demanded that because he wasn't about to pull the reserves from Calet), then you (the Allies) get to meet those German divisions in terrain much less friendly for defense. Southern France would have been much prefferable to the dug in slopes of Italy, and you still tie up those 500,000 German men just the same.

2.) If he doesn't swing around, or if you can disable the Kesserling divisions to the point punching through, then you own the entire left flank of the advancing Panzer divisions on their way to repel the D-Day invasion. Overlord forces and lets call it "Underlord" (a Southern France/Mediterranean based invasion) fight their way in until they hook up in the middle, splitting and/or decimating those German forces.

3.) With Underlord, if needs be, if one simply "wants" to take Rome for the sake of taking Rome, now you come in from the North, past Milan into Verona and drop down; and given you own Northern Africa, Sicily, and the Mediterranean Sea, the remaining Italian based German forces are cut off on both ends, with no routes to resupply.

4.) If the Kesserling Italian based divisions are by and large redeployed to the Eastern Front - because now there is no Italian invasion and Overlord and "Underlord" are yet to occur so there is no need to keep the bulk in Italy - then the Red Army is further and further depleted until, as Jambo said, they are "bled white." Thus reducing the ability for that Iron Curtain to descend post war. Russia would have eventually slogged through the added Kesserling divisions, one way or the other, but now they are that much less of a threat to the West post war given that added depletion of men and resources.

The question is then, why did FDR agree to invading the boot? Surely all of these options were at some point laid on the table after Sicily but prior to the Italian invasion. There is only one answer and it involves the difference in how Churchill and FDR read Stalin. I agree with Jambo's assessment that both Stalin and Churchill's every move was made conscious of limiting eachother's post war sphere's of influence. So my question is why did FDR not see what Churchill clearly did? Jambo mentioned that perhaps Roosevelt wanted the war over and placating Stalin's request for that front aided this. But my question then is, what is the downside to NOT placating Stalin by refusing an Italian front? What would he do? Pack up the Red Army, hand back Kirsk and go home? My contention is that Roosevelt simply did not see "Uncle Joe", as he referred to Stalin, as the threat he clearly was. Churchill did. Thus the Italian campaign went forward based soley on FDR's intent to keep ol' Joey Stalin happy and swilling his potato mash (as his rank and file swallowed potato mashers, I might add). FDR had many shining war time moments, this was not one of them.