
Ch. XV : The Peace of Righteousness http://books.google.com/books?id=Io4fAAAAIAAJ&q=%22The+only+safe+rule+is+to+promise+little+and+faithfully+to+keep+every+promise+to+speak+softly+and+carry+a+big+stick%22&pg=PA537#v=onepage
1910s, Theodore Roosevelt — An Autobiography (1913)