Fred - your last comment is most accurate - the level the 2nd Amendment is supposed to work on is the individual level for the protection of life and property. And that's where we, as individual citizens should employ the 2nd Amendment - at our homes to prevent personal loss through criminal efforts, not to take up arms to prevent civil disorder.
Yes, the Cops and the NG are supposed to restore order in situations like this - if we (citizens) banded together and tried to stop looting or rioting we would be seen as worse than the looters and ciminals - imagine, shooting innocent people trying to survive a horrible tragedy like that - and that is exactly how we would be seen.
If, however, we armed ourselves to protect our families, our liberties and our properties and stayed at our homes or business to do this then we probably would not be seen in such an unfavorable light but hopefully seen justifyably using firearms for personal defense. JMHO. Mikey.