Any nation that expects to be ignorant and free," Jefferson said, "expects what never was and never will be." And if the gap between the educated and the uneducated in America continues to grow as it is in our time, as fast as or faster than the gap between the rich and the poor, the gap between the educated and the uneducated is going to be of greater consequence and the more serious threat to our way of life. We must not, by any means, misunderstand that.

In December 2012 Allegheny County Pennsylvania announced that it would rename the 16th Street Bridge in Pittsburgh in honor of McCullough. " He started it as a book about the founding fathers and back-to-back presidents John Adams and Thomas Jefferson; but dropped Jefferson to focus on Adams. In 2003 the National Endowment for the Humanities selected McCullough for the Jefferson Lecture the U.

McCullough's two Pulitzer Prize-winning books Truman and John Adams have been adapted by HBO into a TV film and a mini-series respectively. McCullough's most recent history The Greater Journey (2011) is about Americans in Paris from the 1830s to the 1900s.