William Gibson has said that he was waiting for the Spook Country book tour interviews to discover what themes the book invoked in readers and reviewers and critics.
Here is one theme, which struck me, perhaps partially as a result of the US edition cover artwork, which features these colours. See the Cover Artwork category archive
Green Gray Black:
Quotations on this theme:
chapter 3 Volapuk
page 16
Brown was snapping on a pair of green latex surgical gloves he'd taken from a pocket.
page 18
Milgrim watched the green-gloved- hand-creatures reemerge, into their limelight bearing something matte, black, partially covered in equally matte black tape.
chapter 6 Rize
page 27
"What's he doing?" Brown took the monocular back. It matched his gun and his flashlight, that same not-color of grayish green.
page 29
They were the same shade of gray, like the gun and the flashlight and the monocular.
chapter 12 The Source
page 57
He saw Brown's pistol and flashlight, beneath Brown's pillow, and a rounded rectangle, beside them, that he took to be a large folding knife (no doubt that same greenish gray).
chapter 35 Guerreros
page 160
As Eleggua opens every road, so Ogun clears each road with his machete. God of iron and wars, of labor; owner of every technology. The numbers seven, colors green and black, and Tito held these inwardly now, as he walked toward Prince Street, the Bulgarian's technology tucked within its handkerchief into the inside pocket of his black nylon jacket from APC.
chapter 69 Magnets
page 288
Someone had sprayed these with turquoise-blue paint, then with a faint dusting of dark gray, then with a dull topcoat.[...]
He indicated two printouts, photographs of a shipping container, a dirty turquoise blue.