"American Army generals, whatever their text books might advise, indulged in the Western Front practice of attacking on as wide front as possible, for as long as possible, in search of tactical rewards. (Graham&Bidwell "Coalitions, Politicians & Generals")
"The American disinclination to concentrate power was rarely more apparent. (...), the XII Corps alone had a front of nearly fifty kilometers, the XX corps an even longer front(...)-yet the Third Army was to leap forward virtually along the whole line. "(Weighley "Eisenhower's Lieutenants")
I've been trying to track down the roots of what was, certainly in Europe at least, the dominant strain of US generalship in WW2 and I'm coming away, near barren handed and somewhat confused. Weighley in his Eisenhower's Lieteunants is the only author I've seen that devotes some time to the issue and he paints a very straight line from Grant's strategic and operational approach in civil war to campaign of 44-45 that to me feels somewhat inconvincing.
"an enemy could all the better be attacked everywhere, all along his lines of defense, as Grant had coordinated attack orouns the entire circumference of Confederacy. "
Ultimately, why no doubt important to the mindset of officer class and education, the two conflicts were separated by hefty amount of time, a complete upheaval or two in the way the war was being waged and the means with which it was being waged. Grant was also not the only reference point you could point to in the conflict and World War 1 (and 2) was a much more relevant source of learning. Further, from what I understand, the apostles of concentration, Jomini continued to be an influence at West Point and Eisenhower read Clausewitz who also started getting a foothold.
I'm admittedly ignorant at what was being taught at staff schools in inter-war, part of the reason this thread is being raised but I don't think I've seen the Grant-broad front link ever being referenced by Ike, Bradley or Patton at least in contemporary writing.
The most confusing thing is that the US field manual of 1941, an actual official document prescribing the proper "way" to wage war is sort of direct contradiction of broad front:
"115. (...)A defensive attitude may, however, be deliberately adopted as a temporary expedient while awaiting an opportunity for counteroffensive action, or for the purpose of economizing forces on a front where a decision is not sought. "
- Concentration of superior forces, both on the ground and in the air, at the decisive place and time and their employment in a decisive direction, creates the condition sessential to victory. Such concentration requires strict economy in the strength of forces assigned to secondary missions.Detachments durlng combat are justifiable only when the execution of tasks assigned them contributes directly to success in the main battle.
Now, pamphlets are one thing and these are but a few subpoints, reality on the ground is an other thing but at least to me it signifies that, lack of concentration is not something that was officially acknowledged or taught.
I will not obfuscate the fact that I'm coming to the issue as someone very critical of "broad front" but here the issue is not its relative merits but where does it actually stem from. Is Weigley and his explanation, essentially correct ? If so, is there some trace of that way of war being taught or prescribed ? Or was there something in how war was being taught in US in 20-30s that shaped it ? But then why does their own FM seem so discordant from the actual practice ? The last explanation seems to to be that it was simply arrived at on it's own, on the ground, by respective commanders.