Regardless of whether Greece leaves, the EMU is in big trouble. The EMU has a huge structural problem, and there's no way out. If the rest of the EU gives in to Greece's demands, Spain will want the same treatment, and after that Portugal, Italy and France as well. Continued austerity doesn't improve the Southern economies either, eventually turning them into Third World countries.
The EMU was never an economically sensible project, it was an idealistic political dream project to some and at the same time a French plan to contain Germany's economic power, and now faces harsh reality. A monetary union in such divergent economies without a full political union was simply a retarded plan, the strong economies will destroy the weaker ones due to a lack of control over national currency valuation, and then they drag down the strong ones with them. At the same time the weak economies abuse the relatively strong currency and low interest rates with irresponsible financial policies.
If Greece exits the EMU their economy will probably start growing after the initial chaos, possibly with deals with Russia and China. Greece is geopolitically important, so even if it doesn't pay off immediately, they'll be interested.
He is right to be fair, Europe needs to unite politically, as well as but not just fiscally. Hopefully that is what will happen.
That's not what's going to happen. The differences between EU member countries are way too big to unite politically. It's completely unrealistic. It's about as realistic as Mexico and the USA joining politically.