The quest to build bridges between Asia and Africa is longstanding. A Chinese Admiral -- Zheng He -- led a series of voyages from East Asia to East Africa, down to Kenya and possibly Zanzibar, from the year 1405. The ships he navigated were enormous -- about 400 feet long and 100 feet wide (122 metres by 30.5m) -- especially when compared with Christopher Columbus' Santa Maria, which was about 70...