How we cite our quotes:
If I should die, think only this of me,
That there's some corner of a foreign field
That is forever England (1-3)
Wars are sometimes fought over small things. In this line, all the speaker's death gets for England is a "corner," which sounds like a really small amount of land. It's hard not to detect some sarcasm in Brooke's lines here. Or do you think he seriously thinks that validates his sacrifice?
There shall be
In that rich earth a richer dust concealed (3-4)
The speaker reminds his audience of one of the grim realities of war. Many soldiers will not make it home, but rather will die and be buried on the battlefield ("concealed").
A dust whom England bore, shaped, made aware (5)
War is destructive. You might even say that it reduces everything to "dust," even people. The speaker unwittingly describes war's destructive power by referring to himself as nothing more than dust.