This is the sum total of what he has to say about the most acute existential threat to the West:

“To reduce our stockpiles and launchers, while ensuring our deterrent, the United States and Russia are completing negotiations on the farthest-reaching arms control treaty in nearly two decades. And at April’s Nuclear Security Summit, we will bring forty-four nations together behind a clear goal: securing all vulnerable nuclear materials around the world in four years, so that they never fall into the hands of terrorists. These diplomatic efforts have also strengthened our hand in dealing with those nations that insist on violating international agreements in pursuit of these weapons.  That is why North Korea now faces increased isolation, and stronger sanctions – sanctions that are being vigorously enforced.  That is why the international community is more united, and the Islamic Republic of Iran is more isolated. And as Iran’s leaders continue to ignore their obligations, there should be no doubt: they, too, will face growing consequences.”

Does he believe this? Does he thing that the international community is more united or that Iran has gotten another year under its belt? His “face growing consequences” formulation could not, if he tried, be a lamer statement of our intentions to deprive the mullahs of nukes. I think we know how unserious he is on this topic. And the mullahs do too.