With regard to winning the war, the ability to win the war was within our capabilities during any 6 month period you might chose to name between July of 1965 and September of 1970. The only thing lacking was the POLITICAL will. Something for which I will NEVER forgive the likes of Walter Cronkite, Dan Rather, Jane Fonda and many others of that ilk!
There’s a lot of people who are burning or will burn in hell for turning what should have been a quick easy war (as much as any war can be) into a long protracted loss. Treasonous press, stupid politicians, and top level commanders (aka politicians with uniforms) without the balls to tell those politicians to stop wasting lives.