Quick—what were the largest ships in the pre-industrial world? Not the Spanish galleons that brought New World silver across the Atlantic; and not the British men o’ war that finally drove those galleons from the sea. Both were outclassed by the “treasure ships” made for the Chinese navy.

First put afloat centuries before those European vessels, the treasure ships ranged far and wide in the 1300s and early 1400s, touching the East African coastline and, some believe, rounding the Cape of Good Hope—unmatched distances for that era. At 7,800 tons, the biggest of these were three times the size of anything the British navy put afloat before the 1800s.

With such a big lead in naval affairs, it seems a wonder that the Chinese never became a sea power on par with latter-day England, Spain, Holland or Portugal. No wonder, though, if you examine history closely.

China’s stint as a sea power all but ended when the Ming Dynasty withdrew support for treasure ship journeys after 1433. From then on, Chinese ships stayed to the east of present-day Singapore. Within a few decades, the initiative in long-distance exploration—and later in trade, too—passed to the Europeans.

The government’s policy shift began when a new faction gained influence in China’s Ming court. Its members advocated a greater focus on domestic and continental matters, emphasizing agricultural production, internal stability, a military buildup and colonization at the edges of the Central Asian steppe, and refurbishment of the Great Wall, designed to repel invaders.

That explains the end of government-sponsored navigation. But, though many think all of China turned inward along with the government, the real story is very different. The curtailing of private sector ocean trips involved more complex factors. Private traders became more active than ever on the Southeast Asian shipping routes but never went as far as the treasure ships had. Unlike the Ming court, private traders based their decision on market forces.

Timber for big boats was expensive, especially in busy trade centers, since large populations meant heavy use of firewood and building wood. China wasn’t alone in the wood shortage. Until coal became widely available as a suitable cooking and heating fuel, Europeans struggled with shortages. All over Europe, as well as in Japan and parts of India, governments went to great lengths to control the price and supply of wood. Venice’s shipyards fell silent for lack of lumber, while the British took extraordinary measures to save theirs, even passing laws that reserved all trees of a certain height and strength in the forests of New England for the Royal Navy. (Enforcing the laws proved to be another matter, though.)

The Chinese government simply let the timber market work. Once the Ming stopped building massive and expensive treasure ships, they paid little attention to timber prices. Their successors in the Qing Dynasty, which held sway from 1644 to 1912, engaged in a short-lived attempt to fix prices during an early palace-building spree but quickly left it to the market.

The market responded by developing a huge private trade in timber, which grew up wherever there was water transport. Logs were floated hundreds of miles from interior forests down all of China’s major rivers and canals to meet the needs of the densely populated regions near present-day Shanghai, Canton and Beijing. Regional centers sent back cloth, iron goods and other manufactures. Wood also moved on the seas, from Manchuria, Fujian and even from present-day Vietnam and Thailand.

But these methods were only good for tapping resources already close to water routes, and coastal and riverside forests were quickly used up. Moving logs from the deep forests used too much labor, so by the eighteenth century the cost of building a boat on the central China coast had risen about three times as fast as the price of rice, China’s staple food, and our most reliable indicator of the general cost of living.

Chinese shippers took the logical, market-driven way out: contracting for construction of boats at various Southeast Asian locations, often in shipyards run by their relatives or other Chinese emigrants. China wasn’t closed, and the market didn’t halt because of artificial factors. There just wasn’t a market for the outsized “treasure ships” anymore.

Instead of financing big ships for long hauls to India and the Middle East, Chinese traders commissioned smaller vessels, capable of carrying porcelain and silk to midway points, where traders would buy Indian cotton and indigo for the return trip.

The shorter routes also fit better with weather patterns, keeping Chinese merchants out of far flung ports where shifting monsoon winds could strand a ship for months. Maximizing profit meant relying on the entrepôts that developed where the winds made it convenient to meet; a series of these meeting places created an efficient marketing network that allowed the exchange of products all the way from the Mediterranean to Japan, China and Korea, without anyone being gone for more than one season.

Deference to the weather proved good business but was a detriment to the development of shipbuilding and open ocean navigation. To make big ships and long voyages worth the investment required ulterior motives, such as missionary work, military competition or the desire to monopolize the seas and bypass the competitive markets in all these port cities. The Chinese left such ambitious projects to the Europeans, who proved willing to defy market principles, thereby launching a new era and pattern for world trade.