Navy Matters Blog (highly recommended) wrote an article covering the logistics of an amphibious assault and the capability of an MEU to conduct one. Read it here.
The problem with the article? The Marine Corps has failed to provide the public...and bloggers, a definition of an MEU's capabilities. This is the best definition I could find on the interwebs, via Military Factory....
The Marine Corps standard, forward-deployed, sea-based expeditionary organization. The Marine expeditionary unit (special operations capable) (MEU[SOC]) is a Marine expeditionary unit, augmented with selected personnel and equipment, that is trained and equipped with an enhanced capability to conduct amphibious operations and a variety of specialized missions of limited scope and duration. These capabilities include specializedThe key words?
demolition, clandestine reconnaissance and surveillance, raids, in-extremis hostage recovery, and enabling operations for follow-on forces. The MEU(SOC) is not a special operations force but, when directed by the Secretary of Defense, the combatant commander, and/or other operational commander, may conduct limited special operations in extremis, when other forces are inappropriate or unavailable. Also called MEU(SOC). See also aviation combat element; combat service support element; command element; ground combat element; Marine air-ground task force; Marine expeditionary force; Marine expeditionary force (forward); Marine expeditionary unit; special purpose Marine air-ground task force; task force.
Limited scope and duration.
That means that an MEU will not be conducting an amphibious assault. An amphibious raid? Yes. An assault? No.
Which brings me to my last point. The MEU while extremely useful, capable and combat proven has to be used wisely. Below is the equipment fit and you'll see that its still a pretty light force....Check out the equipment table here and consider a fictional assault with 4 M1 Abrams MBTs? 15 AAVs? 6 AH-1Zs? Etc....
Marine Corps doctrine states that a Marine Expeditionary Brigade is the smallest unit capable of conducting an amphibious assault....and with good reason.