According to papers from KCC you need police certificate from all countries you lived for more than 6 months. I have lived in US for over 3 years that's why I decided to request FBI background check. I prefer to have all papers on interview even if some of them might not be necessary.
However, it is possible that something has changed and they don't require police certificate from US in consulates anymore. I really don't know for sure.
I would advise you to double check.
If you have interview in April there in no time to request background check from FBI (4-5 months processing time). Try at local police, maybe they can give you some kind of certificate (if you need it).