Because of the proposal president Truman endorsed on equal rights amendment to the United States.
The shortest Wars were: The Spanish-American War of 1898 lasted approximately 6 months; however some historians claim 8 months. Operation Desert Storm (January and Febuary 1991) lasted approximagtely 45 days. The "occupation" continued longer but the War was over in essentially 45 days.
this should help
https://www.britannica.com/biography/Mao-Zedong