In Part IV of this book we saw that Cobden and Perry expressed concern over the imbalance of trade with China. Earls Grey and Albemarle drew attention to the duties on tea being a significant source of revenue to Britain. Herbert, Kinnaird, and Ellenborough spoke of the importance of the sale of Indian opium to China in terms of its contribution to the Indian revenue and to the United Kingdom's global trade. The prime minister defended the opium trade by saying that it helped to balance the trade deficit with China. In view of China's rejection of the British appeal for treaty revision, he wondered what else Britain could do to expand British trade and legalize opium in China. Thereupon Disraeli spelled out what was in Palmestron's mind: to use the Arrow dispute as the casus belli by which to expand Britain's interests in China, where negotiations had failed. Part V substantiated with documentary evidence the view that these spontaneous and brief references point to what were in fact the government's real intentions and concerns.

Part VI quantifies and analyses the basis for these concerns, especially those over Britain's commercial relations with China, in four chapters addressing the Anglo-Chinese trade up to the time of the Arrow War (and in some cases for a few years beyond), China's maritime trade, the problem of India, and finally the balance sheet.