If The Other Wiki is to be believed, then "Model United Nations (also Model UN or MUN) is an academic simulation of the United Nations that aims to educate participants about civics, effective communication, globalization and multilateral diplomacy." That is to say, it is supposed to be Exactly What It Says on the Tin. This... is a simplification. What it really is, is LARPing in suits and being able to pass it off as an educational activity on your college applications. You might want to play Hearts of Iron with hard AI for a more comfortable experience.