How we cite our quotes: (Chapter.Paragraph)
Quote #4
You were born and raised in the good healthy country of Colorado and you had no more to do with Germany or England or France or even with Washington D.C. than you had to do with the man in the moon. Yet here you are and it was none of your affair. (2.22)
Joe really begins to develop an identity around his boyhood and youth in Colorado. It's clearly where his allegiance lies, rather than in some bigger global idea—or even a national one (even though we know he does miss being in America). Considering that World War I was a war between and about nations, Joe's entire reason for being there begins to seem more and more suspect to him.
Quote #5
Oh Kareen why do they have a war right now just when we find each other? Kareen we've got more important things than war. Us Kareen you and me in a house. I'll come home at night to you in my house your house our house. We'll have fat happy kids smart kids too. That's more important than a war. (3.40)
Joe's not talking about the home of his past here; he's talking about the home that could have been. Joe's "death" doesn't just affect him: it affects an entire family that might have lived. Also, notice how Joe keeps repeating the word "house," almost as if the house were a symbol for family.
Quote #6
He knew it was something that had to happen sometime. Yet he also knew that it was the end of something. It was an ending and a beginning and he wondered just how he should tell his father about it. (9.2)
This is like that awkward moment when you're too old for something and your dad doesn't realize it yet—except it's less awkward and more emotional. Here it represents what we lose as we inevitably get older. Contrast this to the way Joe loses everything so early in his life, way before he would naturally have lost those things.