FEDERAL AND STATE AID

Federal Aid So far as I know, the SARS COVAD-19 problem is the first in which the Federal government has been involved.
After the famous San Francisco Earthquake, the Federal Government gave no money to the city for rebuilding. Eisenhower had a hard time getting the Interstate road program through congress until he said it was for military defense purposes
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The item appealed to for the Federal Government to get involved in state problems is called the "Interstate Commerce" Clause [U.S. Constitution (Article I, Section 8)].
The Federal Government getting involved in natural disasters in a state is relatively recent - 1979: The Federal Emergency Management Agency (FEMA) is an agency of the United States Department of Homeland Security, initially created under President Jimmy Carter by Presidential Reorganization Plan No. 3 of 1978 and implemented by two Executive Orders on April 1, 1979.

Today government involvement in natural disasters is common. The governor of the state has to declare a Natural Disaster to start legislation.

Requests for Federal Aid for natural disasters is not always given.  Recent examples involve flooding in Nebraska in 2020 where the damage was not deemed sufficient to obtain Federal Relief.  The sum requested for one flooding was $3 million where it was felt that the state should be able to handle it.

I worked for the Federal government for 34 years and it was very difficult to get Federal research money for many disasters.  Landslides, for example, were considered a local problem and not available for Federal Aid and therefore research.  Earthquake scientists were able to show that earthquakes were not just a local problem but an interstate problem so earthquakes got research money.

 Volcanic eruptions seem to be an exception.  Damage done by the eruption of Kilauea Volcano in the Big Island of Hawaii got Federal-aid even though it is a local problem, but it is complicated because FEMA tried to get its money back from some individuals:
The 100-plus-day eruption covered more than 13.7 square miles in molten rock, destroyed 716 residential structures and displaced more than 3,000 people, according to the county’s website*

State Aid State Aid seems very uneven whether aid is given and is left up to each state. Thus we have some states that never did shut down during the Sars Coronavirus Pandemic although Mayors may have begged for it. Many states refused the increased Medicaid aid of Obama.  Still, states where state aid has been refused, seem to have approval by voters in the state.

* https://www.civilbeat.org/2019/06/big-island-fema-wants-its-money-back-for-aid-to-volcano-victims/