The Holy See and International Relations: Evangelist or NGO?

Why is the Holy See an independent state in international law? More important, why does the Holy See insist upon this? What is the “Holy See” anyway? Does the Holy See’s international relations with states constitute and exercise of the mission to preach the Gospel, or does it compromise it? These introductory questions, along with come contemporary examples, will be addressed with particular attention to the pontificate of Pope Francis.