The power of NATO is that it is a counter, by its mere existence, to Russian aggression against any of its members. Whether or not it has been wisely used against other forces is irrelevant to the protection it offers against totalitarian regimes armed with nuclear weapons.
I don't want WWIII and I don't like Sunni Muslims.
The Kurds have both Sunnis and Shias among them and yet are the most Pro-American group of any in Iraq, actually being the one place in Iraq where our soldiers could travel without weapons and dine in peace. Kurds, in general, love the United States and thank us for liberating them. Just saying you don't like "Sunni Muslims" has no meaning, and I think is just your attempt to denigrate NATO as terrorist supporters so you can claim that it does no good.
The Kurds are the tolerant variety of Sunni. But the Albanian Sunni did not seem to be so tolerant when they were blowing up 1000 year old Serbian churches. Left to their own devices the various Sunni groups would evolve into a new Ottoman empire including all of Ukraine, Georgia, Armenia, Azerbaijan and part of SW Russia. That would be much worse than any alternative I can imagine.