On CNN I saw McCain's acceptance speech at the Republican convention as presidential candidate.
McCain spoke a lot about his Vietnam experience.
Now this could have been very interesting. Because in those days McCain was a navy officer, a pilot who flew bombing missions over North Vietnam. In this role he was simply an agent, executing the orders from his military superiors and (ultimately) the politicians and president in Washington DC. He was a pawn in the game. As president of the USA he will be the one directing soldiers to the battlefield.
So this was a great opportunity to tell the audience that war is hell, that military action should be the very last option, that the Vietnam war was morally questionable (the faked Bay of Tomkin incident), that he -McCain- personally regrets that his bombing missions caused the loss of innocent lives, and that he understands the fury of his North-Vietnamese captors.
He could have said these things, yet he chose not to.