FILE - In this May 13, 2011 file photo, historian and author David McCullough poses at the National Portrait Gallery, in Washington. McCullough's latest book, "The American Spirit," is a collection of talks he has given over the past 30 years. Known for such best-sellers as "John Adams" and "The Wright Brothers," McCullough also is one of the country's most popular speakers, in demand at colleges, historical societies and political gatherings, including a joint session of Congress in 1989. (AP Photo/Jacquelyn Martin, File)