India, Sept. 6 -- When India and Pakistan signed the Indus Waters Treaty in 1960, brokered by the World Bank and hailed internationally as a model of co-operation, it seemed a rare moment of stability in an otherwise fraught relationship. Yet even as Prime Minister Jawaharlal Nehru extended his hand toward reconciliation with Pakistan, a more ominous challenge was quietly taking shape to the north-a China-Pakistan axis that would soon alter the strategic landscape of South Asia. A new book, Trial By Water: Indus Basin and India-Pakistan Relations by Uttam Sinha, brings out how, as the Indus Waters Treaty was being negotiated, Mao Zedong was already casting his eye on a strategic relationship with Pakistan. What Nehru hoped would be a step...