For a long time in history, China and Europe traded through the silk route. At that time, trade means the exchange surplus between trading partners. There is no meaning of open-door or closed-door. Each has its own system running at its own pace.
Then Europe had the industrial revolution. They opened the door of China through Opium War in 1840 to take China into the western system, a system of Suzerain-Colonies global structure. The western powers had gunboats harbored in the ports of China to guard their interest in China. The door was opened by the west for their national interest at the expense of the Chinese people. Chinese people lived in war, hunger, and misery under the domination of western powers. The word Open Door was actually coined by the US. The US policy towards China is called the Open-Door policy since 1900. The Sino-US relationship dominated by the US has been the open-door policy.
In 1949, China got rid of the control of the west. The west closed the door to China with sanctions and blockades. As a result, China was forced to take sides and join the East Bloc dominated by the Soviets. There was no door to open as the Soviet was not a market economy. Nevertheless, East or West, Soviet or America, were all Western systems.
In 1959， China broke away from the Soviets. The door was closed by outsiders. Both superpowers blocked and sanctioned China. China gained true independence, independent from the East Bloc and the West Bloc. But that’s what China wants since 1840. China wants independence first, then an open door.
In 1979, China opened the door again. This time, the open door was under full control of the Chinese people, not like in 1840 when the open door was under full control of the western powers.
The US wants to close the door of China again, through TPP and the “freedom of navigation,” of fighter jet carriers, because the West has no control over the Chinese Open Door.
On the other hand, Xi continues and deepens the open-door policy under the full control of China.
It seems that Open Door is a specific issue for China. It is not an issue for, say, Mexico. The US has full control, or is it? Is building the border wall close-door or open door? Was the fall of the Berlin Wall open-door or closed door?
Trade today is different from the trade of the Silk Route ages before. Trade today is the division of labor in the world economy. It is not a question of playing by rules or not. It is the question of by what rule and who enforces the rule.
For a century from 1840, China was developing slower than the world average. The human development index was the lowest and far behind most countries in the world. Since 1949, China has been growing faster than the world's average speed, regardless the door is open or closed. The human development index increased dramatically. After 1949, Chinese people mastered their own destination. They do not hand their destination to foreign powers.