"Entire", no. "A sizable amount", most likely. They are the ones with training and experience in these matters, not most elected officials.
I spent my career in the Army, most of it in the Special Ops community. I'll tell you right now that most of those who come under a 'sizable amount' and are opposed to it aren't experts at counter-insurgency.
You'll always hear--and I spent a career dealing with this--grunts, squad or platoon leaders and sometimes even company commanders complain about rules of engagement in these situations. They are hampered by a mentality--understandable--mired in a conventional war mindset.
There is a reason privates and platoon leaders don't develop strategy.
You don't like the ROEs? Tough. They are there so you don't kill civilians. You kill innocent civilians and you've just put their family or clan over into the insurgent camp. Now you've made the task harder for future patrols or other units yet to deploy there by creating yet another sniper, mortar team, or even just handing out food to the Taliban.
This is a counter-insurgency, the civilian population is one of our 'targets' to capture; in this case to neutralize the insurgents use of their resources, recruits, intelligence, etc.
The mission is more important than your life. If that means you go on patrol with restricted ability to flatten a village with arty so be it.
McChrystal knew what he was doing (before his staff had a brain-fart) and Petreaus was the architect of his strategy. Counter-insurgencies are not easy to fight, they are complicated, deal with cultural understanding almost as much as military prowess. You want easy become a postman or sell insurance.