re: #194 Dianna

Someone answered above - evidently the line of succession is determined by when the cabinet department was formed.

That explains a lot.

I didn’t see that, but according to Wiki (I know, not always the best source), the current succession is based on:

Presidential Succession Act of 1947

The section after discussing President Pro Tem reads:

(d)

(1) If, by reason of death, resignation, removal from office, inability, or failure to qualify, there is no President pro tempore to act as President under subsection (b) of this section, then the officer of the United States who is highest on the following list, and who is not under disability to discharge the powers and duties of the office of President shall act as President: Secretary of State, Secretary of the Treasury, Secretary of Defense, Attorney General, Secretary of the Interior, Secretary of Agriculture, Secretary of Commerce, Secretary of Labor, Secretary of Health and Human Services, Secretary of Housing and Urban Development, Secretary of Transportation, Secretary of Energy, Secretary of Education, Secretary of Veterans Affairs, Secretary of Homeland Security.