Is it true

[Aramazd]

if you leave the city undefended and it sneaks up on you and you forget about it/can't get a unit in fast enough

happened to me before... but i didn't lost jet fighters, just the city

By the time you have jet fighters you should have rails, and it shouldn't be a problem.

 

[Taras Bulba]

By the time you have jet fighters you should have rails, and it shouldn't be a problem.

just to play devils advocate... it could be a unit w/ 3 movement, and sneak up on a city with no culture, that way you didn't even see it coming... plus, when i have Jet Fighters, i have rails, but it isn't like EVERYone of my cities is connected by then, because i usually have very large territories

 

[Aramazd]

just to play devils advocate... it could be a unit w/ 3 movement, and sneak up on a city with no culture, that way you didn't even see it coming... plus, when i have Jet Fighters, i have rails, but it isn't like EVERYone of my cities is connected by then, because i usually have very large territories

If you don't have rails in all your cities by the time you're in the Modern Age, you're in trouble. I could see if you just captured a city, but then it should be garrisoned.