This website could help answer questions on US citizenship renunciation:
http://travel.state.gov/law/citizenship/citizenship_776.html
In short:
A person wishing to renounce his or her U.S. citizenship must voluntarily and with intent to relinquish U.S. citizenship:
1) appear in person before a U.S. consular or diplomatic officer,
2) in a foreign country (normally at a U.S. Embassy or Consulate); and
3) sign an oath of renunciation
Renunciations that do not meet the conditions described above have no legal effect. Because of the provisions of section 349(a)(5), Americans cannot effectively renounce their citizenship by mail, through an agent, or while in the United States. In fact, U.S. courts have held certain attempts to renounce U.S. citizenship to be ineffective on a variety of grounds
READ ON FOR DETAILS...
Yes, it is very difficult as I stressed to many people on several “Obama isn’t a citizen because of his Indonesian step-father” threads.
You can’t accidentally lose citizenship, it can’t be taken from you, except under the most extreme conditions, and you can only surrender it if you REALLY want to and are willing to jump through a lot of hoops.
I prefer it that way, it prevents mischief by government agencies.
Absent fraud, it should be easier to get citizenship than to lose it.
In Charlie Chaplin’s autobiography he said that he asked American officials why there was so much bureaucracy in renouncing his citizenship. He was told that they make it complicated enough so that it is not something people will do lightly, without thinking it over or if it is not their true wish. Maybe there are other reasons now.