I once had the opportunity to talk to a North Korean defector and this is very similar to what the defector told the group I was with in regards to why people believe what they do in North Korea:
How serious is the brainwashing in North Korea?
When Kim Il Sung died in 1994, I was shocked — I never expected him to die. Because we truly believed he was a god, who didn’t smoke, drink alcohol or go to the bathroom, or [have sex] with women.
Some people criticize North Koreans and ask, Are they stupid? How can they believe those ridiculous things? But I say, It doesn’t matter if you’re smart, if you were born in North Korea you would be exactly like us. We don’t know what freedom is. We have never enjoyed it. We don’t know what democracy is or capitalism. We are completely blocked. Not only from the outside world, but also domestically as it’s not easy to travel around inside North Korea unless you have a travel certificate from the regime. You only have one TV channel — it’s a propaganda channel. We believed that’s utopia because we cannot compare. [TIME]
You can read much more of this interview with Hyeonseo Lee at the link such as how she strongly agrees with the increased sanctions on the Kim regime.