American English has not dominated global English.

American is not a language, but rather English is predominantly spoken in the United States, which is often referred to as American English.

miley Cyrus is American but she can speak English because American people do speak English and miley Cyrus has a American accent

American English is like British English in many ways, but american english is spoken in the United states.

Both English people and Americans speak English, but with differences in vocabulary, pronunciation, and grammar. American English has evolved separately from British English and has its own unique characteristics.