I find that you can see Webb's theme encapsulated in a few brief paragraphs in a work of fiction, the below is from Forrest Carter's The Vengeance Trail of Josey Wales. [BTW-A mighty fine book itself.]
“The [Mountain] Code was as necessary to survival on the lean soil of mountains, as it had been on the rock ground of Scotland and Wales. Clannish people. Outside governments erected by people of kindlier land, of wealth, of power, made no allowance for the scrabbler.
“As a man had no coin, his coin was his word. His loyalty, his bond. He was the rebel of establishment, born in this environment. To injure one to whom he was obliged was personal; more, it was blasphemy. The Code, a religion without catechism, having no chronicler of words to explain or to offer apologia.
“Bone-deep feuds were the result. War to the knife. Seldom if ever over land, or money, or possessions. But injury to the Code meant---WAR!
“Marrowed in the bone, singing in the blood, the Code was brought to the mountains of Virginia and Tennessee and the Ozarks of Missouri. Instantaneously it could change a shy farm boy into a vicious killer, like a sailing hawk, quartering its wings in the death dive.
“It all was puzzling to those who lived within government cut from cloth to fit their comfort. Only those forced outside the pale could understand. The Indian—Cherokee, Comanche, Apache. The Jew.“The unspoken nature of Josey Wales was the clannish code. No common interest of business, politics, land or profit bound his people to him. It was unseen and therefore stronger than any of these. Rooted in human beings’ most powerful urge—preservation. The unyielding, binding thong was loyalty. The trigger was obligation.”