John Kerry lived a sheltered life as a child, he lived in the lap of luxury growing up and spent his weekends as a teen ager with people like John F. Kennedy and the Forbes family who he a cousin to. He went to all the best schools, and planned at an early age that he was going into politics.
Throughout John Kerry's Sheltered life, he rarely was denied his wishes, this treatment is something that is coming back to haunt him now. The main reason for this is because John Kerry has never had to accept the fact that he might be wrong or might not get what he wants. When denied he usually strikes back with a personal attack or a condescending remark that could easily leave the questioner intimidated because of John Kerry's position.
I am no expert on Human behavior, but from everything that I have read about John Kerry, He has never been forced to admit he was wrong, nor has he ever accepted defeat. he has always been given the room to dismiss a defeat or deny a wrong. Without this basic experience of humility, John Kerry does not possess the skills it takes to lead.
John Kerry does not have what it takes to accept advice because he isn't capable of believing that his opinion might not be the correct one, and the mark of a true leader is someone who is willing to accept advice and consider that advice, despite his or her opinion. John Kerry simply lacks these skills and is not fit for serving as our Commander-in-Chief