Should say "She is from USA." As American can refer to many places, it is a continent. . . Well two actually. So someone from Mexico is actually American. Same reason someone from The Congo is African. I understand most of the world says people from USA are American. But they are including a lot of nations in that. And Does it really matter where a person comes from? No one asks to be born where they are born. What an induvidual does defines who they are.