Im with the "A warrior is someone who fights and risks his life for something he/she believes in" group.
I think that a true warrior is someone who follows their ideals and backs them when needed with actions no matter what the cost to themself to protect those ideals.
Now I'm going to say something very contentious here. It is based on the two statements above. There are an awful lot of people we define as terrorists who could easily fit into these definitions. An Afghani extremist who genuinely believes the US must fall, an Iranian who feels the only way his culture can survive is to destroy 'western' society. They both have a very strong belief in what they are fighting for, and the protect that belief no matter what the cost.
To my mind a warrior does not use indirect methods, they are direct and straightforward. It doesn't matter if the enemy knows this because skill and professionalism will compensate.
An interesting point associated with this line of thinking is the Norse berserker, terror weapons of the 9th and 10th centuries. If you read the sagas berserks do not get a great press, they are brutal thugs who are usually overcome by a thinking warrior. And yet today if you asked a person if a berserker was a warrior they more than likely say yes.
the whole Warrior thing has to do with PERSONAL AUTHORITY to me.
A warrior is someone with enough personal authority to ACT when action is necessary. A warrior does not look to OUTSIDE AUTHORITY to tell him WHEN to act. When action is necessary a warrior takes those actions for some personal idea of good. A warrior has personal authority and is moved by that authority.
The opposite, to me, is a Soldier. A soldier is totally commaded and ruled by an outside authority. A soldier has NO personal authority. A soldier points his gun and shoots when ordered. A solider often has limited knowledge or "need to know basis intel" about his actions - he often doesn't even know who he is shooting or why!
A warrior cannot be made to killwithout knowing WHY in very obvious, direct terms.
I agree to a point that a warrior is self-reliant but they are still part of society and military structures and therefore obey orders. A warrior may disregard orders that are blatantly absurd, however. An ordinary soldier may not.
But I think that the US Army, and my own country's army, would disagree with your definition of a soldier. Soldiers are not without minds, they don't kill simply because the orders have been issued. The staggering amounts of propoganda aimed at soldiers during WWII and Korea and Vietnam was designed to put soldiers in a position where they would kill when it was necessary.
In this day and age the term soldier has two very distinct meanings. A soldier is either a very professional, highly trained individual for whom killing is an accepted part of the job, or he is a mindless drone who will do whatever the authorities tell him to. It seems people pick whichever definition suits their needs at the time.
I hold two units as modern day examples of warriors (they're not that modern). The first is the 101st Airbourne based on their magnificent defence of Bastogne 1944. The other is D Company 6th Battalion Royal Australian Regiment who fought and prevailed against more than ten times their number at the Battle of Long Tan in Vietnam 1966. The interesting thing is when you read or see interviews with the men of these units they do not use the term warrior, they call themselves soldiers.