[2][3] Hong played a major role in the development of Chinatown in Los Angeles, helping rebuild the community after it was relocated to accommodate the construction of Union Station in the 1930s.

[7] As an attorney, Hong worked to overturn the Chinese Exclusion Act of 1882, including testifying before the United States Senate on its effects.

[7] The construction of Union Station in the 1930s involved the destruction of the city's existing Chinatown, and Hong played a pivotal role in developing its replacement, the first in the United States to be owned exclusively by its Chinese residents, both as an investor and in offering legal guidance.

He designed a series of buildings on Gin Ling Way, one of which ultimately housed his legal office, and developed the main entrance gate on Broadway and its neon lighting.

[7] His legal practice, the first in Los Angeles owned by a Chinese American, specialized in immigration law, and Hong became one of the top specialists in the field.