You're right. Drop the class.
Seriously, the crap you learn from the class will hurt your life's happiness and earning potential far more than a flag. And by the way, if you think that flag represents one thing, and the displayer thinks it means another, you can tell her politely how you feel. And if she doesn't budge, forget about it. You will meet many people in life who think differently than you do. You want to have a temper tantrum each time that happens, you're in for an unhappy and frustrating life.
And it will ensure that she remains an angry, bitter victim for the rest of her life.