Ya'll keep talking about it so let's run with it. Why I believe the M10 Booker is the wrong vehicle for the needed USMC Infantry Support or Medium Tank...

Ok. Let's go on and have this talk.  Ya'll keep saying that the M10 is the perfect replacement for the Abrams for the USMC.  

I say it isn't.

Let me lay out my reasoning and then I look forward to hearing rebuttals in the comments.

1.  Force Design 2030 is a clusterfuck from hell but I accept that the Abrams was just too heavy.  But to take it a step further I believe that the USMC does NOT need a tank but a dedicated and effective Infantry Support Vehicle!

2.  The USMC ISV should have certain qualities.  The main one being able to swim from ship to shore IF needed.  I don't think the USMC will be able to conduct amphibious assaults for at least 20 years thanks to the damage done to the force but once that capability is rebuilt (assuming the Marine Corps is chosen and the Army doesn't pick up the role), the Assault Echelon will be a thing again.  Having a vehicle that can knock out bunkers/fortifications will be needed.  Oh and rest assured that drones will not find and kill them all.

3.  Money is an issue.  While I have doubts about the ACV, one thing good is happening.  We're seeing the number of vehicles in the GCE being necked down.  If we could somehow arrive at a common engine that would be awesome.  We won't so a similar engine along with drive trains etc across as much of the fleet as possible will drive down maintenance costs and possibly even training.  Taking the ACV and mounting a gun on it would accomplish this.  Even perhaps attempting the 105 on the ARV assuming its survives would be a step forward.

The main thing is that the Booker would be a step toward adopting an Army vehicle to a mission that the Marine Corps no longer performs.

How many times have you heard sustained ground combat talked about lately?  When was the last time you heard the USMC being able to flex up and down the spectrum of combat?  When was the last time you heard anyone mention that the MEU could conduct ops for 15 days unsustained, 30 days for the MEB and 45 for the  MEF?

The new Marine Corps isn't a ground combat force.  It's an auxiliary of the Navy.  Every clime or place no longer applies so to add the capabilities of the Booker is "old" thinking as the current crop of USMC Officer describe.  Even an ISV is probably old thinking.

A true combat force like the old Corps would definitely benefit from the Booker.  The new school Marine Corps is just a bunch of shore watchers and missile shooters.  They really don't even need the ACV is they're being honest.