What is the biggest issue in the middle east and why?

I think currently the biggest issue in the middle east currently is the new found knowlege of iran becoming a nuclear state. this is the biggest conflict because al-queda is a very big threat, and although if iran were to acsess those nuclear weapons they would not directly bomb the united states, but they would bomb people that the united states that are affiliated with them. such as israel, and if they were to bomb it, it could possibly start world war three. also, if iran was to give terrorist's acsess to these weapons, there is really nothing good that would come of that.