If one only read the Al Hanisim that appears in the Shemonah Esray and benching, one would not know much about the miracle of the oil. Perhaps the lighting is a public manifestation of a miracle that is much more difficult to publicly commemorate.
One year when lighting the first candle of Hanukkah with Rabbi Baruch from Mez'ibose' , the flame jumped and disappeared from the candle, with no signs of smoke.
How does the flame, the darkness and the exile connect Hanukkah?
The Chanukah candles teach us that Jewish faith does not lose its strength. To the contrary, despite the hardships and darkness, faith persists, and even blossoms. The refined spirituality that is revealed through the Torah is eternal, and it grows.
The purpose of "darkness" is to present man with a challenge - the challenge of strengthening his faith and uncovering God's presence. Because Joseph faced the trials of faith and stood up to them all, he merited the light of redemption.