Presidents' Day is set aside to recognize the February birthdays of two of our greatest presidents, George Washington and Abraham Lincoln. As we honor them this year, it might be interesting to reflect upon the influence one book -- with its very unique perspective -- had upon the latter, written eight years after his birth.

Additionally, it gives us pause to wonder, had the book been written earlier so as to be read by the former, would it have had similar effect.

Powerful books, read by those later succeeding to national leadership roles, can impact on history. The reader's personal interpretation of such a book ultimately determines whether the effect will be positive or negative. Fortunately, the lesson Lincoln extracted from his book motivated him to undertake action as president that had a very positive impact on the lives of millions.

Lincoln credits three books he read for forging his political thought. Two were religiously oriented -- the Bible and "The Pilgrim's Progress," the latter a Christian allegory written in 1678. Interestingly, neither of these books has ever gone out of print, suggesting their strong influence remains to this day.

But it is the third, non-religious book that generates keen interest as to its impact.

Entitled "Sufferings in Africa," it is the true story about slaves in Morocco, written by James Riley. But the master-slave relationship the book details isn't the one typically perceived by Western readers.

Riley was captain of the U.S. merchant ship Commerce when it was shipwrecked off the coast of Moroccan Western Sahara in August 1815. The crew made it ashore, only to be captured by Sahrawi natives who took "ownership" of them as slaves. Brutally treated, they were forced to march across the desert with little food and to drink their own -- as well as camels' -- urine.

Life was hard for the crew survivors who were worked to the bone and to the verge of death only then to be traded to other tribes or killed.

Eventually, Riley convinced a slave trader to buy him and his remaining crewmembers and take them to a city where he promised the trader would be well rewarded by Riley's associate. The trader did so, not realizing Riley really knew no one in the city who could help.

However, fortune soon smiled upon the crew as the first Westerner -- William Wilshire -- encountered there was from the British Embassy and he quickly arranged for payment to be made so the Americans could be released.

After undergoing such hardship in Africa, Riley committed himself to the anti-slavery issue. He went on to found the town of Willshire, Ohio, named in honor of the man who rescued him from slavery.

Lincoln was probably moved by Riley's account as it gave slavery victims something unique -- a "white face" that detailed their suffering, humility and hardship at the hands of non-white masters. It was a book that personalized slavery to the white man and opened his eyes to the plight of the black man in America.

An American-Indian saying of Lincoln's day was, "Don't judge a man until you have walked a mile in his shoes." Riley's book put the white man in Africa in the shoes of the black man in America. It was this book that was most likely responsible for motivating Lincoln to later sign an executive order freeing millions of slaves.

On Sept. 22, 1862, during the American Civil War, Lincoln warned the rebellious states of the South the emancipation of slaves in any state not rejoining the Union would occur as of Jan. 1, 1863. The basis of Lincoln's authority to execute the Emancipation Proclamation was that held by him as commander in chief. It also allowed him to then authorize freed slaves to become paid members of the U.S. armed forces.

What if Riley's book had been written decades earlier in time for Washington to have read it?

While we will never know that answer, there are indications he may have been similarly moved.

We do know, during his life, Washington often expressed concern about his slaves' welfare and ultimately provided for their freedom and education in his will. Before becoming president, he was pressured by his good friend and fellow Revolutionary War comrade-in-arms France's Marquis de Lafayette to declare "all" men free.

Contrary to Lincoln's effort to permit slaves to serve in the army, Washington prohibited it, later reversing himself on the issue.

Underscoring the need to free slaves in America, Lafayette, during a visit to America in 1789 after the French Revolution had begun and its famous Bastille prison was overrun, presented Washington with a key to the prison as a symbol of freedom for all slaves from all masters. Today, that key remains at Washington's Mount Vernon home.

Lafayette made clear to Washington that had he known a free America would sanction slavery, he would never have assisted in the colonies' fight for independence from Britain.

As we reflect on two of America's greatest presidents this Presidents' Day, let us not forget how the enlightenment enjoyed by a later occupant of the White House, emanating from a book's ability to put human suffering into a personalized context, empowered him to correct an earlier occupant's error in failing to truly recognize that "all men are created equal."

(A retired U.S. Marine, Lt. Col. James Zumwalt served in the Vietnam War, the U.S. invasion of Panama and the first Gulf War. He has written "Bare Feet, Iron Will -- Stories from the Other Side of Vietnam's Battlefields," "Living the Juche Lie: North Korea's Kim Dynasty" and "Doomsday: Iran -- The Clock is Ticking.")

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