"Combat Support" vs. "Combat Service Support" vs. "Service Support"

[TheMarcksPlan]

The below table is from CMH's The Organization of Ground Combat Troops.

Organization of Ground Combat Troops - personnel distribution March 1945.png (62.04 KiB) Viewed 4751 times

It lists three types of support troops: "Combat Support" vs. "Combat Service Support" vs. "Service Support".

Can anyone explain what the dividing lines are here?

[TheMarcksPlan]

Organizing says "combat support" refers "mainly to certain engineer and signal units, considered as combat units in the present table; but it included also a few other units of the AGF services and all military police of AGF type, considered as service units in the present table. It likewise included a small percentage of ASF units." p. 168. That's not a complete definition, however (which ASF units? What proportion of engineers and signals troops? 51% would be "mainly.") And it suggests that categorization of MP's was not always consistent (they're service units in the "present table" but not always?).

I'd also guess that the difference between "Combat service support" and "Service support" involves proximity to front line and/or whether one supplies combat goods (weapons and ammo) or general goods (food, construction, etc.). Those are just guesses.

I've read through most of this book, btw, and several other green books. Haven't seen where a definition is specified. A search for "combat service support" in Organization, for instance, turns up only two mentions - neither providing definitions.

[TheMarcksPlan]

I'll also note that these distinctions also appeared to flummox some in the Army as well:

Exact demarcation had not yet been made between types
of service units which the Army Ground Forces and the Services of Supply
were to activate and train. Duplication and overlapping resulted. The recommendation for service support exceeded the War Department allotment by
385,752. The total excess was about 500,000.

"Precise data," wrote the Chief of
Staff, AGF, "as to the total personnel engaged in the services in the entire
United States Army are not available to this headquarters for analysis. However, from the general information at hand, it appears that over-all production
of services to combat forces is grossly excessive; and some definite measures to
control the dissipation of manpower to these non-combatant functions must
be instituted at once."

...from Organization.

[Richard Anderson]

Combat includes the Combat Arms, in the U.S. Army of World War II that meant Cavalry, Infantry, Field Artillery, Coast Artillery, Corps of Engineers, Combat Aviation of the USAAF, and the new quasi-arms, the Armored Force and the Tank Destroyers. However, the Corps of Engineers also provided combat support, combat service support, and service support roles, depending on the unit and how it was tasked.

Combat support are those units that provide fire support and specialized combat support to combat units. In World War II that included the Chemical Warfare Service, the Corps of Engineers (see caveat above), the Military Intelligence Service, Corps of Intelligence Police (later Counter-Intelligence Corps), and the Signal Corps.

Combat service support are those units that provide direct service support to combat units from the Quartermaster Corps, Ordnance Department, Medical Corps, Transportation Department, Adjutant General's Department, Corps of Chaplains, Finance Department, Inspector General's Department, Judge Advocate General's Department, Corps of Military Police, and Special Services.

Units of those services that did not provide direct service support to combat units provided service support.

[TheMarcksPlan]

Thanks, Richard.

Combat support are those units that provide fire support and specialized combat support to combat units.

Are there any "fire support" roles that aren't combat? Only obvious one would be chemical warfare service.

Combat service support are those units that provide direct service support to combat units
...
Units of those services that did not provide direct service support to combat units provided service support.

What's the definition of "direct" here?

[Richard Anderson]

Yes, the Chemical Warfare Service is the obvious specialty fire support service. "The principal service function of the Chemical Warfare Service is to provide chemical materials and gas defense appliances. In general, chemical weapons and munitions used exclusively by chemical troops, and protective devices and materials for all troops, are procured, stored, issued, and maintained by the Chemical Warfare Service. It is charged with investigation, development, procurement, and supply of all smoke and incendiary materials, all toxic and nontoxic gases, and all gas defense appliances; rehabilitation of salvaged chemical warfare mat6riel; necessary inspections to see that chemical warfare material in the hands of troops is properly stored and cared for; and investigation of any injury or accident resulting from use of chemical materials. The Chemical Warfare Service furnishes the chemical components of chemical munitions used by the arms, all other components being procured by the Ordnance Department which stores and issues the complete munitions. The service functions of the Chemical Warfare Service are performed by depot, maintenance, laboratory, decontaminating, impregnating, and special aviation service units."

"Direct" as in the Service unit is assigned or attached directly to a combat unit, i.e., a combat division, brigade, group, or battalion, or to the corps combat troops of an army or corps, in a theater of war.

Note that the USAAF had "administrative [i.e. service] functions which include procurement, storage, issue, maintenance, and repair of all aeronautical equipment and supplies which are not specifically required to be furnished by other arms or services. Its service functions pertain principally to air force units. Exceptions are all photographic and cinematographic work made from aircraft, including the taking and furnishing to the Corps of Engineers of such aerial photographs as may be necessary in the preparation of military maps; and the operation of the Army weather service."

[TheMarcksPlan]

"Direct" as in the Service unit is assigned or attached directly to a combat unit, i.e., a combat division, brigade, group, or battalion, or to the corps combat troops of an army or corps, in a theater of war.

Thanks Richard. Can you name a source?

[Richard Anderson]

FM 101-10 Administration.

[Leo Niehorster]

Happy Holiday Greetings !
How widespread was the use of the 4.2-inch Chemical Mortar?
--
Leo

[Richard Anderson]

Happy Holiday Greetings !
How widespread was the use of the 4.2-inch Chemical Mortar?
--
Leo

For most infantry divisions in 12th Army Group there were enough Chemical Mortar Battalions for the attachment of one or sometimes two companies during offensive operations.

[TheMarcksPlan]

FM 101-10 Administration.

A gentleman and a scholar.

[Leo Niehorster]

For most infantry divisions in 12th Army Group there were enough Chemical Mortar Battalions for the attachment of one or sometimes two companies during offensive operations.

Many thanks.
--
Leo