Insufficient Data

I tried looking up the story about the disappearance of that family in Chicago.  Apparently a lot of people have disappeared in Chicago over the years.  It would help if I knew the specific year and the name of the family, but I don't.  I probably read about it in the Detroit Free Press, which we have never subscribed to, but copies were commonly found lying around in the break area at the paper mill, where I worked from 1967 to 1990.  I seem to remember that it was part of a larger article about problems that had been associated with I-94, of which there were many.  The lost family had been seen at a gas station or someplace near the Indiana line, and they had not shown up to claim their reservation at a downtown hotel, so it was assumed that they had taken the wrong exit off of I-94.  If I knew it was going to be on the test, I might have taken notes.

I do remember that, when I-94 was first opened to traffic, it was totally gridlocked in a matter of minutes and they had to shut it down for a few days to clear all the abandoned vehicles.  It was the widest multi-lane highway in the world at the time.  There were local lanes and express lanes and, if you got in the wrong lane, you could easily end up somewhere you didn't want to go.  It didn't help that most of the signs hadn't been installed yet on the day the highway was opened to traffic.  Years later, I was coming home on leave after basic training in a Greyhound bus and we were gridlocked right by the 51st Street exit.  I told the driver that I was closer to my destination now than I would be when we got to the terminal downtown, and asked if he could let me off right there.  He said that he wasn't supposed to make unscheduled stops but, since we already stopped, he didn't see any harm in opening the door to let in a little air.  I walked up the exit ramp to 51st Street, where I caught a CTA bus that took me home in short order.

I think that most of the "White flight" from Chicago in the 60s was primarily motivated by fear.  There was also an economic component to it in that, the longer they waited to sell, the less money they would get for their house, but I don't think many of them would have left town if they didn't believe that they would be risking their lives if they stayed in their old neighborhood.  Like I said, the perception of risk might have been exaggerated, but I don't think it was totally groundless.

The Mormons chose Utah because it was not part of the United States at the time.  Their leader had been murdered and they had endured a lot of persecution in the U.S., and they wanted to literally get out of the country.  When Utah was annexed after the Mexican-American War, the Mormons felt threatened by the reported approach of federal troops that had been sent there merely to establish a U.S. presence in the territory.  This misunderstanding resulted in the Mormon War, which probably could have been prevented by better communication.

https://en.wikipedia.org/wiki/Utah_War