I'll leave that up to others. I don't have any idea what would constitute having enough guns and ammunition around. I don't own a gun (and I am a firm supporter of the 2nd amendment.) Just a personal choice.
Respectfully, and to all:
It really does no good to buy, assemble and store goods if you cannot protect those goods.
In a major crisis affecting this country, it's food & water distribution systems, there will be those who will set out to take what they did not store if at all possible. SOme will ask, and some will not ask. It is your responsibility to protect you and yours in the event of crisis. Do not depend on any government, or police agency. They MAY not be there for you. Think ahead, and get some self-defense.