Your correct. I can't think off the top of my head of an Island
in revised that you can attack island to island without an
Aircraft carrier or long range aircraft tech.
There are possibly two places on the board where you can do something like this*. Although you'd be attacking from a land territory to an island in both cases.
1. Panama to the West Indies island. (That's a rare combat.)
2. United Kingdom to the Greenland island, if indeed you consider Greenland an island. (Even rarer!)
...and of course, the US National Advantage Island Bases allows your fighters to pull off island-to-island combat all over the Pacific, even without Long-Range Aircraft tech.