Did the US hold and then claim foreign land as its own post-war? yes
Did they then settle US personal their afterward? Yes
that's colonization, is it not?
so if anticolonialism was not enough of a deterent to prevent the above, why would it be enough to prevent a Hong Kong lease transfer?
Well, first of all, the Okinawans, so far as most Americans were concerned were "Japs," and self-determination didn't apply to them to the same extent it did to, say, the Chinese.
Second, and more important: Okinawa with its bases was part of the US Pacific insular defense network. Hong Kong could not fulfill that function because it was just too close to China. US possession of it would be unnecessary if the US was dealing with a friendly China and--as 1941 showed--it would be extremely difficult to defend if dealing with a hostile one. When the Communists were rapidly gaining control of China in 1949, the US refused to make a firm commitment to the UK to defend Hong Kong because doing that would require the establishment of a "military position well inland" which in turn would require "a movement of large-scale forces into China." Thus, "unless we are willing to risk major military involvement in China and possibly global war" it would be "unwise" for the US to contribute to the defense of Hong Kong.
https://books.google.com/books?id=BGITDAAAQBAJ&pg=PA45
So if the US doesn't want Hong Kong for military reasons, why would it want it? Economic reasons? Hardly anyone in the mid-1940's could foresee the boom in late twentieth century Hong Kong. America would just see Perfidious Albion as dumping hundreds of thousands of impoverished Chinese into Uncle Sam's lap--and then using the transfer to get out of its debts!
The whole idea just doesn't make sense for the US. Some Americans (like FDR) wanted the British to return Hong Kong to China. Others, like Cordell Hull, believed it would be unwise to pressure the UK on this issue; Hull remarked that Hong Kong had been British longer than Texas had been part of the US, and that the US was not likely to give Texas back to Mexico.
https://books.google.com/books?id=x8b4an0T0twC&pg=PA138 But *nobody* wanted Hong Kong for the United States.