I don't recall exactly why Britain did not give the city back or whether they even could but a great account and prophesy of things to come for America in the Middle East can be found in A Peace to End All Peace: The Fall of the Ottoman Empire and the Creation of the Modern Middle East
Fall of Constantinople, whose people would hardly defend themselves at the time (the task falling to Venetians mostly)
I'd strongly disagree with the assertion that it fell to the Venetians, even mostly. The Venetians sent very little, though effective, naval support, and grudgingly at that (show me the money).
I'm not sure what you mean by "whose people would hardly defend
(my emphasis)". The entire population, from slaves to the Patriarch and Emperor (who gave his life)defended that city (and the West) in 1453. I would dare say the then Roman Popes would have done the same thing, being shifty Medici and all.
The martial arts begin and end with respect...