From a purely political standpoint you are correct and I would agree. However from a military standpoint when you go to fight you it does not matter the political issues behind it. That is for the suits in Washington and worrying about things you cannot control whilst in a combat zone is sure to get you killed. So from the standpoints of the soldiers they were told to go here or there and take this objective or that. In that sense they were fighting for America regardless of the actual underlying political issues. They did their job and they did what they were told. No man can be faulted for sacrificing his dreams, pursuits, and sometimes his life to fight a war they don't understand, may not support, and has little control over. When they say go you go and you do so for no other reason than it's your job. Politicians are the ones who make war - the soldiers are the ones who execute it. I have no love loss for politicians but I salute the men and women who put their lives on the line or leave their families for months at a time simply because they are told to do so. All heroes.
While I agree on what you say Bubba, I just don't believe America fought for itself in Vietnam or does in Iraq.