Why is there so many U.K. flags around in the U.S.A and not so many U.S.A flags in the U.K.?

Iam a welsh american living in Cardiff and when i went to America for a while(NE) there was loads of Union Jacks flying high in NYC but when i come home i relised there wernt so many USA flags in Cardiff, the only ones i ve seen in Cardiff are on the HIlton Hotel, the Marriot Hotel, The Welsh embly debating chamber and Cardiff Castle and occacionaly outside St David Hotel. I ve also got an American and a Union Jack on my Wall in my bedroom. Why isent Britain so intrested in America than America is intrested in us?