I stood on a roof top and they wove their cage
Their murmuring throbbing cage, in the air of blue crystal.
I saw them gleam above the town like diamond bolts
Conjoining invisible struts of wire,
Carrying through the sky their geometric cage
Woven by senses delicate as a shoal of flashing fish.

They went. They left a silence in our streets below
Which boys gone to schoolroom leave in their playground.
A silence of asphalt, of privet hedge, of staring wall.
In the glass emptied sky their diamonds had scratched
Long curving finest whitest lines.
These the day soon melted into satin ribbons
Falling over heaven's terraces near the golden sun.

Oh that April morning they carried my will
Exalted expanding singing in their aeriel cage.
They carried my will. They dropped it on a German town.
My will expanded and tall buildings fell down.

Then, when die ribbons faded and the sky forgot,
And April was concerned with building nests and being hot
I began to remember the lost names and faces.

Now I tie the ribbons torn down from those terraces
Around the most hidden image in my lines,
And my life, which never paid the price of their wounds,
Turns thoughts over and over like a propellor
Assumes their guilt, honours, repents, prays for them.

Stephen Spender

http://www.poemhunter.com/poem/on-the-pilots-who-destroyed-germany-in-the-spring-of-1945/