He hadn't decided to. The hum decided. His right fist went past Caleb's ear, close enough to stir his hair, and into the wooden doorframe beside his head with a crack that sounded like a branch breaking. The wood split. Pain went up Daniel's arm to the shoulder, bright and clean and almost welcome. Caleb flinched. He couldn't help it, Daniel saw, the flinch of a man who has learned that loud sudden noises mean the world is about to end. Then he steadied and stood there with his eyes closed and his breath coming fast, waiting for the next one.
There wasn't a next one. Daniel stood looking at the split in the wood and the blood beginning at his knuckles, and the hum drained out of him all at once like water from a tub. What was left felt exhausted, and old, and sick.
He sat down on the top step of the metal staircase with his back to the door and his elbows on his knees. After a moment, he heard Caleb sit down behind him in the doorway.
They stayed like that a long time. Below them the air guns in the tire shop whined and stopped, whined and stopped. A truck went by playing Mexican radio. The late September sun was warm on the metal.