Purpose of the MBT?

[Chris jM]

A question for the more knowledgeable folk out there:

In 'The Human Face Of War' Jim Storr notes that (page 126):

...'the best defence against a tank is a tank' is simply not true. Specialist anti-tank weapons are about 2.5 times better at destroying tanks. Guderin freely admitted it.

Storr goes on further with some more statistics, but the main thrust of his argument is above. this confuses me as I have always being taught that the tank's reason for being is primarily to kill other tanks. I can agree with Storr, but remain confused as to why MBTs are so predominant in many forces.

My early, uneducated thoughts (caveated with the fact that I have no experience with armour):

- MBTs are the most flexible form of armour (as opposed to specialist infantry-support tanks and dedicated missile vehicles), representing the best possible outcome in a trinity of protection, mobility and firepower

- MBTs are the most suitable capability to accompany infantry into the assault and are able to exploit through contested territory better than any other form of AFV.

As such, although they are neither the most suited capability for a dedicated infantry-support task or for vehicle-vehicle combat, they remain the most flexible platform around and because of their flexibility are the most suitable capability for the assault and exploitation functions in any army (which, using Storr's paradigm of combat for those who are aware of it, means that the tank is the most suitable capability we have to create widespread shock amongst an enemy force).

I know some discussion occurred in this thread (http://council.smallwarsjournal.com/...ad.php?t=10546) on the IFV/ AFV concept, however my confusion remains. What is/ where is the utility and value of the MBT?