You wouldn't be seen as a "perpetual foreigner" (gaijin) like that, and American culture is much more lenient on foreigners carrying along their old customs compared to in Japan. Overall I'd expect an easier time, particularly in that it's always achievable to be seen as American (more in some areas than others, especially SV, not to say the US doesn't have any problems with discrimination), but in Japan a foreigner or even foreign-looking native is never truly accepted as Japanese, as pointed out here: https://news.ycombinator.com/item?id=16612178
SV is segregated based on class far more than race or ethnicity. Not all of America is lenient, but more so than any other country I’m aware of (though Canada seems close), anyone can become accepted as a citizen.
