This policy created by John Hay was known as the Open Door Policy.
The goal of this policy would be to allow European countries and America to trade with China on an equal basis. John Hay wanted to ensure that no one country had a monopoly on the trade with China during the early 20th century. Along with this, he felt that the Open Door policy would result in less fights/confrontation between the countries involved in this trade.
Wasn't one of them the 9/11 attack?
The date was July 9, 1755
