I actually think that the concept of the three block war is useful to a point. I agree with the authors’ premise, though, that one force can’t perform all three functions. I’ve often thought that expansion of the military police branch towards autonomous units would go a long way towards accomplishing block 2, COIN or peacekeeping operations. In addition, more direct involvement of other agencies, especially AID, CIA and private contractors would be invaluable in both blocks 2 and 3 and maybe even supersede any military role in block 3. Basically, use people who are suited to roles and damn the bureaucratic pigeonholes.
I am wary of their touting of the UN experience in these things. From my perspective, the UN role in peacekeeping has either been minimal (El Salvador), best credited to others (Australia in East Timor) or horrendous (Somalia and Rwanda).
Each are different tasks, require different skills, training and mindsets. These tasks use support in ways incompatable with the allied tasks as envisioned in the 3 block war.
That said - if the US is to persist in the idiotic notion of “Nation building” than some model is needed.
At the risk of sounding completely cold hearted (and I am in this) let the ‘warring tribes’ sort it out - if you feel bad about the results, then ensure both sides are armed at equatable levels. Giving one or the other the warring parties rifles is better than having US personnel die for something that is of (literally) no import to our Nation.
Once the tribal issue set is sorted out, see if any of the remnants can be salvaged.
The Taliban Mafia filled a power vacuum, the US could have stepped in earlier, I suppose, to assist, perhaps saving a lot of our people and treasure. OTOH we could have ‘carpet bombed’ the poppy fields with some herbicide and killed the source of funding (and power) of the Taliban Mafia.