It is true that what happened in Libya was awful, but don't be a Qaddaffi apologist.
I agree that those who didn't want Qaddaffi should not have supported the violent opposition. Qaddaffi though really would have gone house-to-house. He said so. He promised a bloodbath. He was a dictator. He did attack unarmed protesters. He promised he would before they even started protesting.
That said, the linked article is worth reading. Fact checking all of it would be virtually impossible though.
Also, the report on Syria that the article mostly refers to was not very good. I read the whole thing. It wasn't confidence building in terms of its own ability to properly describe what went on in Syria. I've seen that report's few points highly exaggerated elsewhere. This linked-article doesn't let you know that the report cited very small numbers of incidences and even then, there was no sense that the report writers could be sure who did what.
The writer of the article, Michael McGehee, accuses Gilbert Achcar of being selective. That's ironic. It really feels like the pot calling the kettle black.
What was my position? I was opposed to NATO using any violence. I was opposed to the demonstrators taking up arms. Frankly, when they started in demonstrating in Libya, I thought they were extremely premature: reckless. Well, look what happened. That said, once the war began, I did not want Qaddaffi to win.
Could the US and NATO have not simply bombed and then walked away? Yes. They shouldn't have bombed, even if under the military so-called option. If they were going to do RtoP, they should have landed and created a zone between the East and West. Then they should have caused negotiations -- real ones. They should have had humanitarianism as the highest object.
As for the Responsibility to Protect, per se, it's a lofty idea by secular standards; however, it really can't be done right, again by their standards, without completely locking down a country long enough to totally remake it. Plus, every nation is different. Every people shares aspects with the rest of humanity, but the differences are what matter regarding an undertaking such as global RtoP. What it is, is policing. It should be peacekeeping/making.