In doctrine, therefore, we should always have regard to usefulness, so that everything that does not contribute to godliness shall be held in no estimation. ---John Calvin, Commentary on Titus 3:9.
It's easy to be post-mil in America after the civil war. It's harder to be post-mil after the Great War. Why? Did the Bible change? The times we live in dictate much more about popular theology than people realize.
“Hermeneutics or Zeitgeist as the Determining Factor in the History of Eschatologies?” (JETS 20 [1977]: 45–55)
I'm still postmil after two world wars, the Cold War, and in the middle of this current war with some of the Musselmen. But I don't believe in Heaven on Earth before the Eschaton.
C.M. Sheffield
This speaks to a weakness common to pre and post-millennialism; they are too often drawn into the error of interpreting providence as supporting their own eschatological scheme.