Many have claimed that the Underdark is a terror. Consider this, every race present in the Underdark is far more fierce than those of the surface. This combined with the lack of resources are the proof many give of the Underdark being a terror. I would question this claim of the terror of the Underdark.
First let us consider the lack of resources. We can all agree that many powerful forces are arranged around our city. If resources were truly the driving factor behind everything, how would our city survive today? We are not powerful enough to face the forces around us head on and defend our share of resources if resources were truly as scarce as some claim. I claim that resources are scarce, but not to the point they would drive the carnage we see around us.
Second, let us consider the races around us. Why are they so fierce? We have ruled our resources, the only other common factor is their location in the Underdark. I claim some force in the Underdark itself drives races to become fiercer than is their norm.
The evidence is present in our own city. There are perhaps four or five major factions present in our city. Each contends with the others to gain power to hold onto the power it has gained. The reasoning behind these actions differ but the actions themselves are the same. Yet, all these factions tend to band together to drive off a major threat to the city itself. Finally, each of these major factions has sent out expeditions to destroy threats before they reach the city. What other race behaves in this manner? The answer, though politically unfortunate, is the drow. In fact, the argument could be made the drow are more civilized than Sanctuary itself. The drow tend to offer defeated races the option of enslavement, brutual to be sure but at least the defeated race survives. The war parties of Sanctuary have a tendency to commit genocide upon the races they defeat.
I would note these writing are not given to condone the actions of those races around us in any way, only to point out the reality of our situation. Our presence in the Underdark is changing us, molding us. Some force is at work upon our very souls, guiding us to heights unimagined upon the surface. - Given in My Own Hand, Kadin