July 28th, marks the 150th anniversary of the adoption of the 14th Amendment of our Constitution, which defined American citizenship. Martha S. Jones is the Society of Black Alumni Presidential Professor at Johns Hopkins University. She was formerly a founding director of the Michigan Law School Program in Race, Law & History. She is an author, and her new book, directly related to the 14th Amendment--Birthright Citizens: A History of Race and Rights in Antebellum America. www.marthasjones.com