Isn't it obvious that the U.S. and the U.N. are separate bodies already? This is the U.N.:
http://www.un.org/Overview/unmember.html
You put in your argument, in the same sentence, that 'we' the United States are responsible for the deaths. If 'we' had so much power over the U.N. then there would not be any discussion over IRAQ right now because it would have already been over. Why not tie that list to the deaths too instead of singling out the United States like the typical propagandist would do and has done.
The U.S. is not playing a dominance game. It just wants to get rid on one tyrant with war crimes history in the Middle East. Getting rid of a mental leader is not playing dominance (more propaganda). The U.S. has the military capabilities to take over Canada and Mexico at the same time, do you see the U.S. doing that? In the young history of the United States, when have we ever attacked another country just for the sake of conquering it?