I read this last night and I will read it again this morning and maybe add some more. here was my impression:
1) It's very powerful
2) The Tet Offensive is a wonderful subject for a poem, especially considering your background
3) The cricket at the end was GREAT.
1) It's too long
2) too many patch-ins, and less YOU. When you speak with your own voice, it's very intense and moving.
3) The title: again, a patch in. Also, it announces that whoever is going to read this poem will feel sad. Why do you want to announce your purpose? It neutralizes the emotional effect. "Tet" would be a perfect title, just like that.
gosh you are GOOD! But the phrase that comes to mind is: "The Kingdom of God is within you." When you speak from your gut, without thinking of any other writers, or stuff written on Coke bottles, you flatten me like an atomic bomb ...
... I just read it again, and memory served me correctly. Consider shortening it. Consider omitting some of the patch-ins. Also, the beginning (do you remember?) probably doesn't need to be there