This is a print from a magazine or Capitol Hill photo-book.  Obverse is hand-signed by Harry Truman, and reverse is signed by a number of senators.  Probably obtained by a Capitol Hill visitor.  Truman can be considered the first man in history who by a single decision of the will, set in motion the eventual demise of over 200,000 people with the dropping of the first atomic bombs on Hiroshima and Nagasaki.