In his book, Mr Hitchcock raises another issue that rarely features in euphoric folk-memories of liberation: Allied looting, and worse.
"The theft and looting of Normandy households and farmsteads by liberating soldiers began on June 6 and never stopped during the entire summer," he writes.
One woman - from the town of Colombieres - is quoted as saying that "the enthusiasm for the liberators is diminishing. They are looting... everything, and going into houses everywhere on the pretext of looking for Germans." Even more feared, of course, was the crime of rape - and here too the true picture has arguably been expunged from popular memory.
According to American historian J Robert Lilly, there were around 3,500 rapes by American servicemen in France between June 1944 and the end of the war. "The evidence shows that sexual violence against women in liberated France was common," writes Mr Hitchcock.
"It also shows that black soldiers convicted of such awful acts received very severe punishments, while white soldiers received lighter sentences." Of 29 soldiers executed for rape by the US military authorities, 25 were black - though African-Americans did not represent nearly so high a proportion of convictions.
After reading the last paragraph a question arises: In the U.S. military forces, did black soldiers suffer a heavy racial segregation as late as World War II?