Do not confuse "duty" with what other people expect of you; they are utterly different. Duty is a debt you owe to yourself to fulfill obligations you have assumed voluntarily. Paying that debt can entail anything from years of patient work to instant willingness to die. Difficult it may be, but the reward is self-respect.
Robert A. HeinleinThere are a dozen different ways of delivering destruction in impersonal wholesale, via ships or missiles of one sort or another, catastrophes so widespread, so unselective that the war is over because that nation or planet has ceased to exist. What we do is entirely different. We make war as personal as a punch in the nose. We can be selective, applying precisely the required amount of pressure at the specified point at a designated time. We've never been told to go down and kill or capture all left-handed redheads in a particular area, but if they tell us to, we can. We will.
Robert A. HeinleinA community where everyone is a ruthless murderer, with handy access to death-dealing devices, is a very polite community.
Robert A. HeinleinThe commonest weakness of our race is our ability to rationalize our most selfish purposes.
Robert A. Heinlein