I'll not address Byrd but I will say I'm not in favor of the US becoming "pre-emptive". Other than that Byrd and I don't agree on much.
However......
WWI was successful form the allied war aim point of view. Armies returned to their homelands and the killing stopped. It was the "peace" that was porked.
WWII was extremely successful, particularly from the point of view of the "undesirables". The peace was well done with regard to the former enemies. It was the former allies that porked peace.
Korea? Again, incredibly successful. Simply compare North Korea to South Korea. The war was fought to prevent the North from conquering the South and instituting the "living death" form of existence that the North now enjoys.
VietNam? That's peace? You must have forgotten the military adventures of the "new" VietNam after the South was conquered. I'll wager VietNam's neighbors would have something to say about the "peace". I think Kennedy's original intent was fine but even he was getting ready to pull out when he was assassinated. It was LBJ that made the huge goof ups. Shouldn't have stayed; when he did, he should never have tried to run it himself with the help of Robert STRANGE McNamara.
Ask yourself why the Gulf War requires a sequel. It's not like SH wasn't totally whipped militarily last time. It doesn't need a sequel because of any military failing. It needs a sequel because the "coalition" didn't have the political sand to do what needed to be done. And they set it up that way from the beginning. The never was a "replace Saddam" war goal. Right there's the failing, because it could easily have been done. So, while the war went well and was successful, it can only achieve what the politicians set as goals.
Just some thoughts.