Why do the US and the UK still interfere in the internal problems of other countries?

when doing that breeds hatred and extremism ,the result of which is terrorism attacks on their nations http://uk.news.yahoo.com/22/20100104/tts-uk-yemen-ca02f96.html please excuse any spelling mistakes /grammatical errors as English is my third language and one i use only rarely your patronising attitude is uncalled and of no value i do NOT live in a third world country [...]