The China-Pakistan axis plays a central role in Asia's geopolitics, from India's rise to the prospects for a post-American Afghanistan, from the threat of nuclear terrorism to the continent's new map of mines, ports and pipelines. China is Pakistan's great economic hope and its most trusted military partner. Pakistan lies at the heart of China's geostrategic ambitions, from its take-off as a global naval power to its grand plans for a new silk road connecting the energy fields of the Middle East and the markets of Europe to the mega-cities of East Asia. Yet Pakistan is also the battleground for China's encounters with Islamic militancy, the country more than any other where China's rise has turned it into a target. For decades, each side has been the other's only "all-weather friend", but the relationship is still little understood. The wildest claims about it are widely believed, while many of its most dramatic developments remain closely-guarded secrets. This book explains the ramifications of Sino-Pakistani ties for the West, for India, for Afghanistan, and for Asia as a whole. It tells the stories behind some of the relationship's most sensitive aspects, including Beijing's support for Pakistan's nuclear program, China's dealings with the Taliban, and the Chinese military's planning for crises in Pakistan. From China's involvement in South Asia's wars to the Obama administration's efforts to secure Chinese cooperation in stabilizing the region, it traces the dilemmas Beijing increasingly faces between pursuing its strategic rivalry with India and the United States, and the imperative to address a terrorist threat that has become one of the gravest dangers to China's internal stability.