It is estimated by the Red Cross that 3% or fewer of Americans are prepared in any serious way for an emergency. In most emergencies, it will take days for organizations to arrive, even if they do arrive.
For catastrophic emergencies, it could take longer than that.
For national or global emergencies such economic disaster, the aftermath of electromagnetic pulse (EMP), epidemics or war, aid may simply never arrive.
If you think the onus of preparation is on your community, your church, your county, state or federal government, you will become part of the problem. You should instead be the solution to your own problem so that you can participate in becoming the solution to your fellow's problem.
In an emergency, but especially a total one, the order of survival resources is water to drink and stay healthy, protection of self and resources, food to keep healthy and have enough strength to work on securing all four and knowledge to keep the first three going on a long-term basis.