Mystery Unknown President

An alien is found to be suffering delusions....he thinks there is a planet called Earth, and that that planet has a president....

...but which president?

That depends on what decade you read the tale.

1950s

In Mystery In Space #30 (February-March, 1956), with a story by Otto Binder, Carmine Infantino and Joe Giella (with a cover by Gil Kane), the patient alien has delusions of Earth, under a President Izen-Hower (Dwight D. Eisenhower).

Such is the first case of The Impossible World Named Earth!

1970s

When the tale by Binder, Infantino and Giella was reprinted in From Beyond The Unknown #17 (June-July, 1972) with a cover by Murphy Anderson, the delusional alien got to see visions of Nee-Xon (because Richard Nixon was now President, and DC, trying to hide their reprints, changed to the current President).

Making this a second case of The Impossible World Named Earth!