It was interesting to see lessons about coalition war in Afghanistan to be applied to the new/old war in Iraq/Syria. It was nice to see an appreciation of the difficulties that caveats impose on effectiveness, as countries place limits on what their contingents can do. That the solution is to engage in minilateralism, leaving out those with significant restrictions, is not surprising ... especially since it was penned by a former Cheney aide. Such folks tend not to see the tradeoff between legitimacy and effectiveness.
But an understandable omission. Less understandable is focusing on inter-agency coordination. Are we setting up provincial reconstruction teams in Syria/Iraq or this mostly a kinetic exercise? If the latter, then the whole of government stuff is mostly irrelevant. Yes, there is a need for coordination among agencies but we are not asking other countries to engage in a whole of government effort, are we? This is not Afghanistan.
Relying on less capable partners is problematic, but given that the US spends far more on its military, it should also have only less capable partners. But less does not mean incapable. And some allies have different capabilities, such as other avenues of intel, better COIN practices, and so on.
The authors harp about intel sharing, but who will the US trust given that many allies in the area have more than one agenda in play? yeah.
The complaint moves on to command and control. Absolutely a problem. The US failed in 2010 when the Marines insisted on their own chain of command. Expecting allies to give up national control of their contingents is just silly. The democracies especially are not going to give up civilian control of the military to a foreign power.
Good luck with the detainee issue. Allies used to trust the U.S. to hold onto those swept up during a peacekeeping operation or conflict, but Guantanmo, Abu Ghraib, rendition and torture made that politically impossible. So, it is unlikely that "this thorny issue must be handled up front."
The problem I really have with this piece is that it mostly identifies real challenges that are mostly inherent in multilateral warfare and only wishes them away. No good lessons learned here about mitigating such challenges. The good news is that it means that the conclusion of our book has not been overcome by events.