How secure was USSR's control of East Europe - Berlin wall

What were living conditions like In West Berlin?

Whilst USSR has stripped industry and resources from lots of East Berlin for reparations, USA had invested a lot in West Berlin.
People on the East side were drawn to West sides wealth and freedom.

Propoganda causing Berlin wall?

People wanting to leave East Germany made the Soviets look unpopular.
Communist ideology looked weak compared to capitalist west.

How did the Brain drain cause the wall?

Those who left East Berlin were mostly the young, the educated , and the people in skilled jobs.
This caused a “brain drain” in East Berlin.

How many people left East Germany between 1949 and 1961?

2.6 million people, 15%

Why did the USA not respond to the construction of the Berlin wall?

Made soviet invasion less likely,
Still had access to West Berlin,
Made communists look heartless and their ideology look unpopular.