Answer:
The primary reason the US advocated the Open Door Policy was to protect and broaden US trade with China. This policy was put into effect in the early 20th century after the Boxer Rebellion in China. It hastened the end of the last dynasty in Chinese history.
Hello there!
Big Woes for the “Little Magician”:
1. Van Buren followed Jackson's coattails right into the White House, but Van Buren was no Jackson... Jackson was the people's president, a common guy himself.
2. Van Buren was very smart, crafty, experienced, and effective, but he lacked the "people's touch" and personality of a Jackson. While on the other hand, Old Hickory personified the rising "New Democracy."
..hope I helped!