I'm willing to give my life for the US. I may not agree with all of what the government does, but it is my government and it is my duty to defend it.
Of course, if it goes too far, it is also my duty to overthrow it.
Annoying conflict of duties, isn't it?
Now, if you asked if I'd give my life to save my wife, my son, or my step-son I'd have to say, in less than a heart beat I would.