USMC Amphibious Combat Vehicle. Direct or Indirect Fire Variant?

The USMC has its ride going into the future.  The BAE/Iveco SuperAV.  Much to my surprise and happiness we also got word from the program spokesman that they're already looking at a family of vehicles starting with the 1.2 "upgrade".  While it will essentially be identical to the ACV 1.1 with 95% commonality, it will feature a few tweaks to allow greater power generation etc...

But what has me thrilled is one variant already being discussed for version 1.2. 

It was called a "gun model".

What exactly does that mean?  I'm really not sure but I'm assuming they're talking about a large caliber gun.

Ok awesome right?  Maybe.  It does bring us back to a subject that we've been discussing quite a bit on the blog.  What happens to Marine Tanks.  Do we need to supplement them with a Mobile Gun System?  Do we need to replace them with Mobile Gun System?  Do we need to neck down to an all wheeled combat vehicle fleet?  If so why?  Oh and before you simply dismiss tanks and the M1A1 operated by the Marine Corps remember this.  No matter how good a sensor suite you put on an ACV it will never have the armor protection of an MBT.  It will never be able to mix it up in close combat like a tank.  Hiding behind an ACV when rounds are flying will pale in comparison to doing the same with a 70 ton monster that is able to shrug off Heavy Anti-Tank Missiles across it's frontal arc, much less small arms fire.

But back on topic.

Do we need to go to an all wheel force and push for a Mobile Gun System?

The Japanese appear to be heading down that road with their Marine Corps and we know the Italians are thrilled silly with their Centauro 2's.

But just because others are doing it doesn't mean that its the proper use of limited funds.  We have heavy firepower and shock already in the Marine Corps.  Perhaps we should take a blast from the past and reinvest in a lost capability for our early entry amphibious forces.  Do you remember the vehicle below?

The LVTH-6 (and its base vehicle the LVTP-5) had relatively short service lives for Marine Corps vehicles.  But they did provide the bridge between the WW2/Korean War models and the LVTP-7 (later called the AAV).  While the vehicle types in the Marine Corps have been basically set for generations we did at one time have a heavy mortar variant in the LVTH-6 that served us well.  The 105mm Howitzer could put down an impressive amount of fire for its time and it had quite a respectable combat loadout of munitions (151 rounds) as well.

Which brings me to the point of this whole thing.

As much as I like the Japanese MCV and Italian Centauro 2, I think we're well served by Tanks Battalion in the Marine Corps.  I believe that you can't beat the firepower and shock that a 70 ton beast brings to the table and with APS the M1A1 with proper upgrades will be viable into the future.

Why duplicate something that we already have in service?

I think the better option would be to get a heavy mortar variant...a turreted mortar variant!  My operating rationale is simple.  I can't get out of my mind the after action report of a Ukrainian Infantry Officer who saw his command wiped out and how he was on the receiving end of steel rain from hell.  I'll try and find it, but his story of having to escape and evade while being pursued by enemy dogs and infantry, ducking when he heard a UAV overhead etc...is the stuff of nightmares.

Indirect fires is the new hotness.  We don't have enough and rely too much on aerial assets for our suppression mission.  This isn't a slam on the wing but what I believe to be a hole in our doctrine. We could correct that by buying the right gun variant of the ACV.

I believe it should be an indirect fire Amos turret mated to the ACV instead of developing a direct fire 120mm cannon version.

That's my opinion though.  What do you think?