Re:OTOH, there's jury duty... (Score 1)

There's no insistence from the US to give up your previous citizenship when you become a US citizen. The State Dept even has a page about it:

http://travel.state.gov/travel/cis_pa_tw/cis/cis_1753.html

This is really just a matter of practical policy ; it's impossible to police and some countries have no process for renouncing citizenship (others, such as Singapore, require you to give up your Singaporean citizenship if you ever take citizenship of another country). The only requirement the US has is that US citizens enter and leave the country on their US passport.