“The two main factors for you will be the terrain and the tribes. You have to know their game and learn to play it, which means you first have to understand their environment,” Professor Akbar Ahmed told me in May 2006. In the field, with military and civilian teams and local people in locations across Afghanistan and Pakistan at various times through the next three years, the wisdom of Professor Ahmed’s insight came home to me again and again. The fact is that the terrain and the tribes drive ninety percent of what happens on the Frontier, while the third factor, which accounts for the other ten percent, is the presence of transnational terrorists and our reaction to them.
But things seem very different in Washington or London from how they seem in Peshawar, let alone in Bajaur, Khyber or Waziristan—in that great tangle of dust-colored ridges known as the Safed Koh, or “white mountains”. This is a southern limb of the Hindu Kush, the vast range that separates Afghanistan (which lies on the immense Iranian Plateau that stretches all the way to the Arabian Gulf) from the valley of the Indus, the northern geographical limit of the Indian subcontinent. The young Winston Churchill, campaigning here in 1897, wrote that “all along the Afghan border every man’s house is his castle. The villages are the fortifications, the fortifications are the villages. Every house is loopholed, and whether it has a tower or not depends only on its owner’s wealth.”
 Winston L. Spencer Churchill, The Story of the Malakand Field Force: an Episode of Frontier War, Thomas Nelson and Sons, London, 1916, p. 273