Palin in an interview claimed she has an insight into Russian politics because you can see Russia from Alaska. Thus the joke.
The issue was not the back porch, it was the stupidity that seeing the land gives one insight into it's politics.
I thought it was pretty clear who the bumbling idiot is. Fey did not come with this gem by herself. She just took it to the next level based on the great raw material. That's what comedians do.
"The Alaska-Russia controversy erupted in 2008 when ABC's Charlie Gibson asked Palin, "What insight into Russian actions particularly in the last couple of weeks, does the proximity of this state give you?"
Palin said: "They're our next-door neighbors. And you can actually see Russia from land here in Alaska."
The debate continues on the Web: several sources say Russia can be seen from a small Alaskan island, but others argue it's impossible to see Russia from the Alaskan mainland, as they say Palin has implied.
Comedian Tina Fey, playing Sarah Palin during a skit, joked that she could see Russia from her house."
http://www.politicsdaily.com/2010/11/01/sarah-palin-you-really-can-see-russia-from-alaska/
I thought people on this forum were able to make the mental jump of two steps at a time. It seems like I was mistaken and from now on will go to the trouble of identifying every little step from one point to the other. My bad.