Why don't Americans have British accents?

America was founded by British people, but why don't Americans speak with a British accent? OK, I know the time can cause a variation, but let's see Australian people still speak British accent (with little variation, but not as much as American English)

Well for one thing, America is a melting pot. We have people from all over the world coming to our country and breeding like wild animals.

There was a large influx of Germans into the US in the 1700s and 1800s. This along with the French and the Spanish all influence our version of English. Another reason: "...some varieties of American English are closer to the English of Shakespeare than modern Standard English is. Some "Americanisms" are actually originally English English expressions that were preserved in the colonies while lost at home (e.g., fall as a synonym for autumn, trash for rubbish, and loan as a verb instead of lend)."