It’s a bit MPSIMSy but I’m curious.
What a fascinating question.
Since they don’t buy insurance, I’m guessing ‘No’ and that they left it “In God’s Hands”.
Seems unlikely. They were probably informed of the location of public fallout shelters. Not all that many people constructed private fallout shelters. And it’s well known that in the event of actual nuclear war, there won’t be enough room in the shelter for everybody, so to avoid living with the guilt of leaving some to succumb to fallout, everybody will leave the shelter and die together. Except me, I’ll be last in line, and slam the door shut as soon as the next to last leaves.
Did you ever read that Fallout comic that Penny Arcade did?
No, but checking out the web site it appears to deal with the post-apocalyptic world. The fall out shelter world always ends before the fallout actually arrives. So I consider it irrelevant to my absurdality.
Say what now?
Private fallout shelters were actually rare. There were fallout shelters for various government officials and some fallout shelters that were just the basements of public buildings, but few people built their own shelters. They were much more talked about than actually built:
We had a well stocked root cellar. I expect they do too.
hence no need for a fallout shelter
Not exactly. Properly, a fallout shelter has to have some provision for protection against radioactive dust, such as a ventilation system that filters all incoming air. A cellar or deep basement would be better than nothing, but you still need all the supplies for an extended stay- water, food, waste disposal, etc.
The college I went to (Texas A&M University) actually had a handful of fallout shelters when I was there, though I believe they were pretty much all used for other things (notably, there was a fallout shelter in the basement of the Military Science Building that housed an indoor firing range, though we could only fire .22 down there.) I recall another one under the North Side Post Office, which for all I know was probably used for storage or utilities or something.
And of course, campus folklore said that the Academic Building (big old-fashioned domed building in the middle of campus) was the first building built with concrete, and as a result, they didn’t know how strong the material was and built it as if it were a brick-and-mortar building, with very very thick walls. This supposedly made it an ideal place to seek shelter in the event of WWIII, because the building was believed to be nigh-indestructable. 
Oh; I’m making no claim as to the effectiveness of such protection; I’m just stating what I expect the Amish would be thinking back then. In my root cellar days we weren’t well schooled in the finer details of adequate fallout protection and I’m making the assumption the Amish were similarly knowledgable.
What valuable targets were there in Amish territory that the Soviets would have attacked?
Fallout can travel hundreds of kilometres from the site of the blast.
So the answer to your question is “New York City”.
Nevermind all of that.
What about the really important issue?
Were they big enough for their horses?
Predominant wind on the east coast tends to be west to east, so the proper answer would be either Colorado or Chicago … New England gets New Yorks fallout…
Or closer to home, Carlisle.
Is the War College all that prime a bombing target?
Heh. I once worked with a woman who grew up in Amish country (but wasn’t Amish herself), who said that Amish men usually ranked, in order of importance, their (1) children, (2) horses, and (3) wives.