I think one of the most noticeable features of his war poetry is the sense of deep indignation and fury. Note his comment on the Menin Gate Memorial:
On Passing the new Menin Gate
by Siegfried Sassoon
Who will remember, passing through this Gate,
The unheroic Dead who fed the guns?
Who shall absolve the foulness of their fate,—
Those doomed, conscripted, unvictorious ones?
Crudely renewed, the Salient holds its own.
Paid are its dim defenders by this pomp;
Paid, with a pile of peace-complacent stone,
The armies who endured that sullen swamp.
Here was the world’s worst wound. And here with pride
‘Their name liveth for ever,’ the Gateway claims.
Was ever an immolation so belied
As these intolerably nameless names?
Well might the Dead who struggled in the slime
Rise and deride this sepulchre of crime.
This was written in 1927 and the fury is still unabated.