China continues to astonish the world by the speed and scale of its economic growth. In less than four decades, it has emerged not just as the factory of the world, but as an economic giant that the Organisation for Economic Co-operation and Development predicts will overtake the US as the world's largest economy by 2016. One thing is clear: the world's two superpowers need each other. They can and should build on their growing inter-relationship to promote global peace and stability and improve the livelihoods, not just of their own people, but across the world. China has the potential to be a force for tremendous good in the world. Already, it is using its considerable fiscal reserves to invest heavily in economic and transport infrastructure in Africa and Latin America, supporting the construction of roads, railways, ports and mines. While some see this as a strategy to gain access to the many strategic commodities that China needs to feed her growing industrial and manufacturing industries, I am not so cynical. It is my hope that China will demonstrate ethical as well as economic leadership in the developing world and not turn a blind eye to governmental corruption and exploitation of the natural environment. The ties that increasingly bind together the US and China are broad and deepening. The US is China's second-largest trading partner after the European Union; reciprocally, China is the third-largest trading partner of the US, after the EU and Canada. In the 2011/12 academic year, around 194,000 students from China were studying in the US, more than double the level of 10 years ago. China is the leading source of foreign students studying in the US who are an important contributor to post- graduate research in many fields. The number of Chinese immigrants in the United States has grown each decade since 1960, from a mere 100,000 to reach 1.8 million in 2010. Chinese-born citizens represented the second-largest immigrant group in the country in 2010. It is vital to keep building this ever expanding network of economic and personal ties between our two countries. It is a key to greater mutual understanding and trust. In geographical terms, Hong Kong is a speck on the world map and a tiny part of China, but we have always punched above our weight. Hong Kong remains a crucial bridgehead in the overall US-China relationship. As of June last year, 333 regional headquarters, 536 regional offices and 519 local offices had been set up by US companies in Hong Kong, the largest group of foreign companies using Hong Kong as their regional business hub. In terms of tourism and despite the economic downturn, the US remained Hong Kong's fourth-largest source of incoming visitors last year. In the 2011/12 academic year, around 8,000 students from Hong Kong were studying in the US, making Hong Kong the 16th-largest source of foreign students in the US. One of my most cherished hopes for my country is that, over time, China can evolve peacefully into a nation where basic human rights are guaranteed and where every individual has an equal right and opportunity to influence how and by whom he or she is governed. There is no doubt in my mind that Hong Kong can play a key role in helping to chart a course towards more democratic government in mainland China. In order to play this role, Hong Kong must remain true to itself and the rights and freedoms enshrined in our constitution, the Basic Law, under the concept of "one country, two systems", namely: the rule of law and an independent judiciary; freedom of expression, including freedom of the press; freedom of religion; freedom from arbitrary arrest and imprisonment; and zero tolerance of corruption. Under the Basic Law, we are promised the right to elect our head of government and legislature by means of universal suffrage, and this will hopefully be achieved by 2017 and 2020 respectively. However, many in Hong Kong fear that the concept of universal suffrage may be fundamentally compromised by means of controlling the method of nomination to the office of chief executive and ensuring that groups of pro-government vested interests continue to enjoy special rights to election to the legislature. Sadly, it seems that the central government still may not trust Hong Kong people with the right to choose by whom they are governed, unless it can be sure that the person they choose will toe Beijing's line. I am an optimistic person, but I am dismayed at the apparent inability of the Hong Kong government to lay down a blueprint for necessary and long-overdue constitutional change. Strong and decisive leadership on this issue is essential. It is my sincerest hope that my country's central government will support and not hinder this development, but rather look on Hong Kong's constitutional development as a potential blueprint - however gradual - for change on the mainland. I have the benefit of living in an open, pluralistic, tolerant society, rooted in the rule of law, personal freedom, clean government and sense of fair play. With each day that passes, I learn never to take these values for granted. Within the wider framework of "one country, two systems" and "Hong Kong people ruling Hong Kong", we are perfectly capable of shaping our own destiny and continuing our unique contribution to China's future growth and modernisation. The coming century will no doubt be shaped by an increasingly affluent and influential China. It is my earnest hope that, in this century, the leaders of my country will have the vision, the courage and the confidence to aspire to greatness - not just in economic and military might - but in every sense of the word. The ultimate test of true greatness lies in how a country and its leaders treat their own people. The world will be watching. Anson Chan is a former chief secretary of Hong Kong. This is an extract from the 2012-13 Rama S Mehta Lecture titled "My Country, My Hopes" delivered at the Radcliffe Institute for Advanced Study, Harvard University, February 21, 2013