Context.

Michelle Malkin once wrote:

I’d like my toddler singing "gook, gook, gook" or "sambo, sambo, sambo"...

Does she really? No, which you'd know well enough if I provided some context.

The "baby mama" business is a different kind of context. You'd think Mrs. Malkin -- who is venomous but not stupid -- might notice a difference between using a term with love and affection and using it with hatred. The delivery in this case is every bit as important as the messenger.