Much like the thread for the most German influenced city, what city do you think is the most influenced by Japan?
Los Angeles: One of the largest Japanese populations in the United States, outside of Hawaii. Architecture throughout the city is a mix of modern and post-modern, Japanese culture is present all throughout L.A., not just in Little Tokyo but even in Hollywood. Sushi is a popular cuisine, and other health related lifestyles.
San Francisco: Another city with a large Japanese population, and the center of a high-tech hub area. Golden Gate Park includes a Japanese garden, and there is a Japan-town, as well as it's neighbor, San Jose.
Seattle: Yet another city with a large Japanese population, downtown architecture is similar to that of Japanese cities, and also technology oriented. There is a famous Japanese garden park there, as well as the International District which includes a lot of Japanese restaurants and groceries. There also Japanese department stores and specialty shops in the regular malls there. They also have a few Japanese festivals in the city.
San Diego: Also a fairly large Japanese population. Balboa Park has the Japanese friendship garden, the Kearny-Mesa area has a lot of Japanese grocery stores and restaurants, the city is also similar to the port city of Yokohama, which is its sister city.
New York City: Large Japanese community, but I think Tokyo is more influenced by NYC rather than the other way around. NYC gets a few Japanese department stores.
Honolulu: A lot of Japanese influence, largest Japanese population of any city in the U.S.