It is the increase in the lethality of, to simplify, the explosive charge.

A battleship would still be somewhat viable today if the explosive was black powder from before the 20th Century.

But since 2 Fritz X 1400kg guided bombs sunk battleship Roma, you can’t have a battleship with 500mm steel armor all around the citadel and still be able to float.

For those who are interested in history the contest between shield and missile has been going back and forth since the copper and then bronze age that we know of and undoubtedly since rocks and wicker shields.

For those of you who remember snowball fights, anyone remember dousing snowballs in water then making them iceballs, putting them in the freezer to increase their kinetic lethality?

Anyone remember snowball fights and snow forts?

Maybe AI can make a better snowball….

The next step to Skynet.

China even has EW capabilities built into some of their newer missiles. They apparently got the idea from reading the “Honor Harrington” space-navy novels.

There are missiles with pif paf propulsion for high manueverability at large % of its range.

And how does decreasing armor thickness affect tank crew morale? Knowing that you are in a tin can that has say 50% chance of NOT intercepting a projectile… hm. Projectile effectiveness depends to a large extent on which part of the tank it hits, so the chances of survival will likely be much lower in the 10-25 ton vehicles.

The suggested attempt to “optimize” tanks will lead to more casualties – higher speed of lighter vehicles will not help against modern guided systems. All this in order to reduce the production and transportation costs, a nasty trade-off.

I’m not sure this would work the same way as it does for the Navy (smaller rocket boats instead of carriers). More likely, it will make recruitment harder and vehicles more dependent on other army units – for example, you will need large radars that need lots of power for counter electronic measures.

Certainly, an army needs light vehicles, but having a big guns is also a huge boost to troop morale, and being in a big tin can is more secure in most cases, which includes artillery protection and hits on the thick armor parts.

Gat also fails to recognize the implications of his own emphasis on electronics. Why would any smart military build an expensive (albeit lighter) manned tank instead of building a flock of cheap smart robot vehicles for the same total cost?

And Gat completely ignores the central point — which is why would a belligerent choose to fight on the front lines instead of simply cutting off the head of the snake by precision bombing or nuking the opponents Political Class?

In the current US/NATO proxy war, Russia’s rulers seem to have decided to let the Ukrainians keep on beating their faces into the Russian fist instead of risking global thermonuclear war by attacking Kiev, London, and the DC Swamp. But it is by no means certain that other rulers or other countries would observe the same restrictions on their actions.