Challenging the integrity of the non-proliferation regime is a matter which can affect international peace and security.
You don't get the fox to be in charge of the chicken coop. You don't give the outgoing regime - which has been practicing dictatorship, is an authoritarian system, it's a bunch of military people - the task of changing Egypt into a second republic, a new Egypt with democracy, freedom, rights, etc.
Nuclear proliferation is on the rise. Equipment, material and training were once largely inaccessible. Today, however, there is a sophisticated worldwide network that can deliver systems for producing material usable in weapons.