If anybody had suggested in 1988 that Germany would be reunited in 1990, he would've been laughed at. Heck, even in February 1989, Eastern German police still killed a guy who wanted to flee to Western Germany. I'm German, I was around 15 at the time, and I thought reunification was never going to never happen - or at least not any time soon. Once things start to change, change often happens much faster than anybody expected. IMO the big difference between NK and Easten Germany is that NK has the atomic bomb. But Eastern Germany also hat lots of Russian soldiers stationed there, and hardly anyone believed that Russia would let Eastern Germany and the other Warsaw Pact states slip away. Otherwise, the situation is somewhat similar: the main supporter state is no longer as supportive as it used to be (and also no longer quite as strict about communism) and there's a prosperous sibling state next door.