Hi,
I'll reply based on each of your specific worries:
(1) Can I travel to the US with my American passport and just my Dominican cedula with out having to pay taxes when I leave the D.R. or must I have both passports? I recommend traveling with both passports, but only use your American Passport when entering and exiting DR and the US. Why? For starters as an American you have entry into the us without having problems at immigration about your Dual Citizenship. Secondly, you just don't need a Dominican Passport. Its worthless... Thirdly, and the only reason why I recommend traveling with it, its just in case when you arrive back to DR with your DR Cedula. The DR Immigration request more proof of citizenship. This will avoid you from buying the Tourist Card.
(2) I am also a Dual Citizen, and the US cannot reject ANY US Citizen the right to International Assistance. Especially when this person is an American Citizen and born within US Soil. Now, I do highly recommend not committing a crime or other illegal activity, as US protection cannot be guaranteed. Under those conditions, you will be judged as a citizen and not a foreigner under foreign policy protection.
(3) To renounce your US Citizenship is crazy. Why??? You have no problems traveling in and out of the DR, with a US Passport. If you renounce you are losing many privileges and moreover protection from the US, in the case of a national incident, crisis or other.
Let me recommend not worrying about it. Travel with both passports and cedula. Use only your US Passport for Travel (to and from) and once you arrive in DR, show only you DR cedula. Like I said above, the DR Passport is worthless and should only be shown to prove DR Citizenship. They should NOT stamp this or you will have problems exiting the country on your next trip. Passports must always show and Entry and Exit, and if two different passports are stamped you will have problems exiting the country, until resolved.
Hope this helps.
I am a native American citizen living in the dominican Republic. I have been here for 2 years and 5 months and have dual citizenship American/Dominican. Can I travel to the US with my American passport and just my Dominican cedula with out having to pay taxes when I leave the D.R. or must I have both passports? Also, can American officials cause me any problems because I have dual citizenship? The American embassy webpage says that they do not encourage dual citizenship because if there is an interntional incident between the two countries the US may not be able to help the citizen. It does not say that it is illegal, simply not encouraged. Also, it states that in order to lose your American citizenship you must submit documents stating that you want to renounce your American citizenship which I did not do. However, you know how people always have horror stories that may or may not be true. I plan to travel in 2 months and don't want to have to worry or any surprises.