What are the similarities and differences between a state government and a regime?

The Oxford
English Dictionary defines a regime as "a government, especially an authoritarian
one." It defines a state government as follows:

The
government of a nation or state; now specifically (also with capital initial(s)) the government
of one of the states of the United States of America, the Commonwealth of Australia, etc.
(sometimes as distinct from the federal or national government).

The two terms do not align perfectly, so we need to look at what each one connotes or
implies. The terms are alike in referring to the governance of a country or territory.

A regime, however, implies a country ruled by a top-down, tightly controlled central
government. An authoritarian government is not usually democratic: it does not reflect the will
of the governed but instead imposes its will on them, whether they like it or not.

In contrast, the existence of state governments implies a dispersal of power away from
central authority and into local hands. The definition's examples of state governments in
democratic nations, such as the US and Australia, suggest that state governance is a bottom-up,
democratic affair in which the sources of power are local and closer to the people being ruled.
While state governments certainly have the potential to be authoritarian, they nevertheless
represent a dispersal of power that works against centralized authority.