The root cause of closed doors.

The fundamental reason: the rulers of the Qing Dynasty adhered to the policy of "agriculture-oriented, emphasizing agriculture and restraining commerce". The self-sufficient feudal economic stability made it unnecessary for people to have too much contact with the outside world. Pretending to be a big country in China and standing still has seriously affected the progress of China.

Extended data:

Positive effects of closing doors:

1 To some extent, it has cracked down and restricted rampant maritime smuggling and piracy.

2. It has played a positive role in the stability of coastal areas.

3. It has played a certain role in self-defense against the aggression of western colonialists.

Second, the negative impact of behind closed doors:

1, the long-term implementation of this policy has hindered Sino-foreign relations, affected China's absorption of advanced culture and science and technology, isolated China from the world, and seriously hindered the budding development of capitalism. China derailed from the world and slowly fell behind it.

2. Culturally, economically and scientifically, it is impossible to keep up with the world, and it is difficult to develop various advanced technical concepts, showing the empire dusk phenomenon as a whole. It is one of the important reasons why China has been beaten behind in modern times.

3. Reduce opportunities for contact with the outside world. Hinder the national economic development and completely lose the initiative in foreign trade. Obstruct foreign scientific and cultural exchanges, and even hinder the development of productive forces and social progress.

4. Initiate international conflicts. Affect the development of social science and technology. It restricts the development of foreign trade and shipping.

Some scholars also pointed out that closing the country to the outside world was actually a derogatory term imposed on the Qing Dynasty by the western invaders, which reflected the western countries' opposition to the false accusation that the Qing Dynasty ignored the facts and was exclusive. They also pointed out that even the ports of western countries at that time only allowed domestic ships to enter and exit, and domestically imported goods were only allowed to be shipped by domestic ships or ships from the country of origin. This was called "protection policy", but it was a double standard to force other countries to open their doors, let them leave freely and monopolize.