Übergeek 바둑이:  Your fourth interpretation does seem the most plausible, considering what else we know of history and how governments often encourage one government over another to keep the lessor one in check.  But that interpretation still validates my point.  Such approaches never fully work in the long run.  They are the wimpy way out.  And there were many signs that such an approach to Germany was akin to letting a tiger out of its cage.

As for Chamberlin, he clearly was weak in his approach to Hitler.  When a country such as Germany, makes a promise and then breaks it, then makes another and breaks that one too, it's not rocket science to figure out that there's a fox in the hen house.  

As for: "They appeased Hitler because they hated communists more than they hated Nazis.  It was a simple as that."

Nothing in world politics is ever simple.