What is the most likely reason Churchill regularly brings up negative details
about the war, such as the German victory in the Battle of France?

Explanation:

I think the most likely reason Churchill regularly brougth up negative details about the war is: A. He wants Britain to have realistic expectations about the future. As a great strategist, Churchill focused on the evidence given by other battles, like the German victory in France, to learn from his enemy.

b. the passage of the equal rights amendment  

explanation:

this mean that anything that someone else could do they could do