Analysis of Tri-Colour

Poppies, you try to tell me, glowing there in the wheat;
    Poppies! Ah no! You mock me: It's blood, I tell you, it's blood.
It's gleaming wet in the grasses; it's glist'ning warm in the wheat;
    It dabbles the ferns and the clover; it brims in an angry flood;
It leaps to the startled heavens; it smothers the sun; it cries
    With scarlet voices of triumph from blossom and bough and blade.
See the bright horror of it! It's roaring out of the skies,
    And the whole red world is a-welter. . . . Oh God! I'm afraid! I'm afraid!

Cornflowers, you say, just cornflowers, gemming the golden grain;
    Ah no! You can't deceive me. Can't I believe my eyes?
Look! It's the dead, my comrades, stark on the dreadful plain,
    All in their dark-blue blouses, staring up at the skies.
Comrades of canteen laughter, dumb in the yellow wheat.
    See how they sprawl and huddle! See how their brows are white!
Goaded on to the shambles, there in death and defeat. . . .
    Father of Pity, hide them! Hasten, O God, Thy night!

Lillies (the light is waning), only lilies you say,
    Nestling and softly shining there where the spear-grass waves.
No, my friend, I know better; brighter I see than day:
    It's the poor little wooden crosses over their quiet graves.
Oh, how they're gleaming, gleaming! See! Each cross has a crown.
    Yes, it's true I am dying; little will be the loss. . . .
Darkness . . . but look! In Heaven a light, and it's shining down. . . .
    God's accolade! Lift me up, friends. I'm going to win -- my Cross.