Words matter.
If you speak another language, have you noticed that how you think changes depending on the language you think in? When I think in English, I tend to be pretty independent in my actions and thoughts. When I think in Japanese, my benaviour and thoughts become much more aware of and responsive to social hierarchy. My body language becomes a lot more contained. When I think in French, my thoughts change and my body language becomes a lot more expressive and my hands become part of my speech.
So many people seem to think that "It's just a joke", or, "You shouldn't take what I said seriously" means that it's okay to say things that belittle or demean entire segments of the population. This could be a political group, another race, another gender, or any group of people that isn't "us" or "them".
The problem is, when we repeat something often enough, we internalize it. We begin to believe it subconsciously, then consciously. For example, I knew a young man once who referred to every woman as the word for a female dog. He thought it was just words and was completely shocked when he was called out on it. He didn't even know he was doing it, but you could watch his actions to see that he considered women to be beneath him. After being called out on it, he began to use the B word less, and his actions towards women began to be less dismissive as well.
If we don't have a word for a concept, we have a hard time wrapping our heads around it. Once we have a word for it, we begin to internalize the concept. Linguists worry about languages dying, not because a culture might be lost, but because a concept might be.
Think about the words you use. Think about how they affect the people around you.
Words matter.