Originally Posted by You
On a side note, is a visa required for US citizens to make port calls in Turkey?
No, so long as you are leaving with the ship.
In Istanbul, you have to fill out a "Turkish Landing Card" that's distributed by the ship when you go ashore and supposedly collected when you return, but they never have collected mine. Also, the published rules say that the landing card is valid only for travel within Istanbul.
In Kusadasi, I don't recall any restrictions as to where one could not travel.