If there is a "Marine Division" in the AEF
Carl Schwamberger;10622848 - The 2d Div was not a combined army Marine organization?.[/QUOTE]
If there is a "Marine Division" in the AEF, beyond the 2nd - presumably the 4th (5th and 6th Marines, 6th Marine MG btn) and 5th Marine brigades (11th and 13th Marines, 5th Marine MG btn) are joined, according to the OP - then said division needs (to match the AEF TO&E) at least a field artillery brigade headqaurters, three artillery regiments (2 btns each), a third MG battalion, an engineer regiment, a signals btn, etc. The 2nd Division presumably gets an infantry brigade and MG btn made up of RA elements from the US, drawn from one or more of the 1918 divisions...
My take on the 2nd Division as it was historically is it was an army division with (at times) a USMC CG and six Marine rifle battalions (of 12) and one Marine MG battalion (of 3).
The suggested "Marine" division would be something less than an army division with Marine attachments and more a Marine division with Army and/or Navy attachments, in terms of organizational culture - not unlike the various French "Division Bleus" over the years...
Thinking about it, presumably the CEC could provide the engineer regiment, and the USN could (probably) come up with enough men for a 155 regiment (of two battalions; maybe they are USN-manned 152s?); the third MG btn and the four battalions of 75s (or 76s, I guess) would be challenging, but a mix of marines, sailors, and soldiers might be enough to get it into the line by the time of a spring 1919 offensive - seems well-positioned to be the vanguard unit across the Rhine, certainly.
Presumably Lejeune commands the division, Neville and Cole the infantry brigades...
Couple that with the 1st Division converted to paratroops idea, and its VARSITY, circa-1919...Patton has to command the tanks, of course.
Interestingly enough, there's an official history of the Marines in WWI, in which the following is included:
November 11, 1918 - The US Marine Corps totalled 72,920 officers and men, of whom 24,555 were serving with the American Expeditionary Force in Europe, with 2,073 on sea duty. The rest were serving in the Azores, China, Guam, Haiti, Hawaiian Islands, Nicaragua, Philippine Islands, Porto Rico, Santo Domingo, Virgin Islands, with 37,043 in the United States.
Presumably could get a division out of that by the spring of 1919, plus additional recruiting...
Here's the link - at least two USMC officers commanded army infantry regiments in the AEF, beyond those of the 4th Brigade, as well...
http://www.naval-history.net/WW1NavyUSMC-aChronology.htm
Best,