People
Remember men, you are fighting for the lady's honor; which is probably more than she ever did.
— Groucho Marx
Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The speaker rallies the troops to fight for a lady's honor, then undercuts the pep talk by adding that she probably hasn't shown much of it herself. The joke is the sudden sting in the tail, turning a noble cause into a cheap shot.
Context reviewed