Conversation so far:
When was Otto Von Bismarck dismissed by Wilhelm II, German Emperor?
In 1890.
Who replaced Otto Von Bismarck after he was dismissed?
Bismarck resigned at Wilhelm II's insistence in 1890, to be succeeded as Chancellor of Germany and Minister-President of Prussia by Leo von Caprivi.
what reason did  Wilhelm II, German Emperor have for dismissing Otto Von Bismark?
Wilhelm wanted to preclude the emergence of another Iron Chancellor.
Had Otto Von Bismark done anything that Wilhelm II, didn't like?
Bismarck wished to form a new bloc with the Centre Party, and invited Ludwig Windthorst, the party's leader, to discuss a coalition; Wilhelm was furious to hear about Windthorst's visit.
Didn't wilhelm II, German emperor  want peace?
He brashly wanted to play the part of the supreme warlord.

Question: The reversal of policy in what?
Self-contained rewrite: Wilhem II, wanted the reversal of what policy ?