Individually, he and I as soldiers over there can make the decision that it is worth the price: our lives.
I can't, however, personally make the cold calculus that is is worth an indefinite number of future (others') American lives.
I assume you are speaking as an idle spectator or philosopher, not as an active member of a society.
As a citizen of America who volunteered for the military and voluntarily took the oath of office to defend and obey.....it is no longer your choice whether or not you and your friend will participate. That is a moral, ethical, and legal position. To do otherwise, to not participate, risks grave consequences including death by a firing squad.
I can't, however, personally make the cold calculus that it is worth an indefinite number of future (others') American lives.
For any orderly society to defend itself against those who are trying to destroy it someone must have the authority, morally, ethically, and legally, to do exactly that. If you aren't up to it, and it is obvious you are saying you aren't, then step aside for someone more capable of command.
What is the cost of freedom? We are fighting a determined enemy who numbers in the millions and will only be satisfied with our total destruction. Do we live up to their expectations and pull out as in somalia, lebanon and vietnam and leave our allies to the wolves? China is funding and using the jihadis to strike at us. If we have no will to fight this war, what will we do when confronted with a more technologically advanced china?