What is a Guerilla's Center of Gravity and Critical Vulnerability(ies)?
Strategic Level? Operational Level? Tactical Level?

Here is an example at Strategic-Operational Levels:

WWI, German East Africa. Col Lettow-Vorbeck and his German and Askari defense forces face overwhelming odds presented by the combined British, Belgian and Portuguese forces arrayed against him. Yet they where never 'beaten.' The Center of Gravity for the Germans in EA was their resolve, their will to resist. Note the main goal of Lettow-Vorbeck was not necessarily defense of the Colony but to draw the maximum enemy force possible into Africa and away from Europe. The critical vulnerability at the Strategic-Operational levels was simply Germany itself. Lettow-Vorbeck's force was small mobile and capable of prolonged guerilla resistance, no longer relying on the Colony for support, tying up thousands of troops and large amounts of war material. This resistance could have been continued for some time past the Nov 11th 1918, Lettow-Vorbeck stated he could resist indefinetly, but when Germany lost the war in Europe, his will was broken, their no longer existed a reason to resist.

Mao Tse Tung had a similiar will to resist as his COG. You could kill thousands of his supporters, force him to march a thousand miles, but his resolve remained. What was his CV? What could have broken the Communist insurgency at the Strategic-Operational levels?

I state (it seems obvious) that the global insurgent's COG is his will to fight, this would definetly apply to the levels of war. In this sense, what then is today's guerilla or insurgent, in the global war's, critical vulnerability? This applies to the trans-national insurgent not the local, who would have a different CV all together based on his local conditions.