Go into the casino in Tanzania's largest city, Dar es Salaam, and what strikes you? The fact that the overwhelming number of players are Chinese. If the Chinese are not quite everywhere in Africa, their numbers, investments and trade have mushroomed over the past 10 years. If one compares Chinese and US investment in Tanzania, there is no contest.
China has been in Africa before. The first time was also in Tanzania, when it came in 1970, complete with a workforce, to build a new railway. For years, the railway has been short of money, its locomotives ill-maintained and subject to breakdowns. The Chinese are now trying to bring it back to life.
Unlike the US, France and Britain, China has never tried to establish military alliances or bases in Africa, but its provision of arms has been a long-standing policy - first as aid to liberation movements, and later as a commercial enterprise.
In its latest attempt to engage Africa, both the tone and size is different. There are probably a million Chinese living in Africa. China has become a major participant in UN peacekeeping in Africa. Trade between Africa and China increased in value from US$10.6 billion in 2000 to US$166 billion in 2011.
According to a new book, China and Africa: A Century of Engagement, by David Shinn and Joshua Eisenman, economic ties between China and Nigeria, for one, have grown phenomenally. "New deals, investments and agreements occur regularly," they said, and up to "600 Chinese companies and joint ventures operate in construction, oil and gas, technology, communications, manufacturing, services and education".
But Chinese activity is not just at the top end of economic life. In Lagos, Africa's biggest city, the Chinese trader community lives and works in a large red fortress resembling the Great Wall of China.
Chinese small-time traders are to be found in many African countries, often causing resentment as they cut prices and expand businesses at the locals' expense. In Zambia, there were violent riots at a Chinese-owned copper mine over working conditions and pay. The issue became an important one in the subsequent general election. In Nigeria, their activities have led to the collapse of the textile industry. Tanzanians complain about the growing number of cheap and counterfeit products.
China's purchase of raw materials has become an important export for many countries. It is almost entirely raw materials to feed China's booming manufacturing.
China will be an important part of Africa's future. Undoubtedly, the relationship will broaden and deepen. Other investors in the West, India and the Arab world will have a hard job keeping up with it.
Jonathan Power is a syndicated foreign affairs columnist