Keep the West out
The way news and information get presented to us is interesting. No matter who presents the news, they have a point of view they are trying to push or perhaps even an agenda. I like to ponder a bit over what is being sold and how.
The former Soviet Union did this all the time. They were in complete control of the flow of information, as all communist, social and totalitarian regimes want to be. When it came to Berlin, after WWII, they had some problems. In the 1950's they had control of part of the city while the U.S., French and British portions of the city had been merged. The part under Soviet control was in a deep depression while the other part of the city was beginning to thrive.
For a time many workers would work in the west and live in the east. There was no wall then. People started to notice that the Soviet so-called "worker's utopia" was not that at all. Many people simply walked across town and never returned. That was a problem... What happens when you have no workers? So they started a campaign of building a wall. It popped up almost over night. They then told the west (us) that it was to protect themselves. They were protecting themselves from the invasion of workers from the west trying to get into the workers paradise they had created. Which way did all the guns and guard towers face? Who actually believed there story? How many people died trying to get into East Berlin? Apparently many nieve politicians in our country did.