About duty. Legally speaking one has no obligation to "repay" the United States of America for providing the most forward thinking, freedom loving, tolerant, protected, and protective nation on earth. Heck you don't even have to be a citizen in order to garner all the advantages (and actually avoid a few of the disadvantages) this nation offers.
About those who died. I personally knew too many of them. Don't worry, they didn't know you, or die for you. You normally live your life in ignorance of what they do, where they go, or the hardships they endured whether in peace or war. Since neither group knows each other; What did they die for? The ideal. The ideal of a free nation where you can be a rugged individualist, an atheist, gay, homophobic, poor, rich, or any other goal you can list. The ideals of a place where you can basically do as you please so long as you don't hurt other people. Or, as Ronald Reagan put it "'the shining city upon a hill". They embody the ideals in their core values. For the Army it was "Duty, Honor, Country". For the Marines and the Navy it is "Honor, Courage, and Commitment". Not sure what the Air Force lists as it's core values, but I am certain they embody the ideal. So don't feel bad about living a hedonistic lifestyle if you so choose. You don't owe anyone a debt. It's already been paid.
Now, according to history, nations rise and fall in cycles. When the citizenry no longer respect the ideals of the nation well enough to subordinate a portion of self interest for the greater good; The nation begins to decline. Someone on the board wrote that rights were not given by government. True. But consider that those rights may be granted by god but they are protected or stolen by men.
What does all the above have to do with Casey Sheehan and the other honored dead whose names you won't be troubled to know? I hope it just serves as a simple reminder of the basic ideals of the country for all of us. Not just your or my personal self interest. I guess that if you've never played team sports or worked as a member of a team you simply won't get it. Even on a team where you "donate" a bit of self interest in order to accomplish a "a whole greater than the sum of it's parts" there is still room for the unselfish individual (a maybe even a selfish one or two).
Did that answer your question? Did it make sense? It's been a reeeeeeallly looooong day, so the brain is moveing faster than the fingers. If you don't get it, ask. I'll follow up tomorrow.