Back in the mid-19th century, some American entrepreneurs sailed halfway around the world - to China - to make their fortunes. These merchants would later build dynasties back home by investing money in promising American industries, including railroads and coal, as well as new technologies, like the telegraph.

It was the invention of the clipper ship that made it all possible. These were ships that were built for speed and profit, a profit that came not just by importing goods like tea to the U.S., but also by smuggling opium to China.

We talk with Steven Ujifusa, a historian and author of “Barons of the Sea: And their Race to Build the World’s Fastest Clipper Ship,” about these vessels - which once raced across the ocean - and the owners who used them to reshape America.