Ming dynasty and Xinjiang 1. Why didn't the Ming dynasty buy new products after the founding of the people's Republic of China?

Since the Tang Dynasty, the economy in the northwest has been seriously declining, and it is unable to provide logistical supplies for the management of the western regions. In addition, the shift of the economic center of gravity to the south and the rise of the Maritime Silk Road have greatly reduced the interest of the western regions in the rulers of the Central Plains. Before the rise of the late Jin Dynasty, the Ming Dynasty always regarded Mongolia as a menace, and all its energy was concentrated on the northern border, so it was impossible to be distracted from running the western regions. The dynasties that ruled the western regions: Han, Tang and Qing all moved westward to rule the western regions after controlling or defeating their opponents on the Mongolian Plateau.