Why was Wonder Woman's character unique and complex? How liberating was she as a character?

Wonder Woman was unique in large part because she was a woman. When the vast majority of the superheroes in comics were male, empowering a woman with superhuman capabilities made a liberating statement about female empowerment. This statement was particularly meaningful at the time of her debut in 1941; in the midst of World War II, women were barred from combat, but characters like Rosie the Riveter showed that society was beginning to consider women to be an important part of the war effort. Having Wonder Woman able to tangle with even the toughest of men reaffirmed the strength of American women in the face of the Axis threat.
However, Wonder Woman was much more than a female clone of Superman. She came to America from Themyscira, a fictional island populated solely by immortal female Amazons. Yet her militant upbringing was tempered by her role as an ambassador to "Man's World." Later incarnations of Wonder Woman would wield sword, spear, and bow, but in her original version, her most significant belonging is her Lasso of Truth--a tool to allow the consummate warrior to resolve conflicts without resorting to war. Throughout her entire history, but particularly in her earlier appearances, this dichotomy of war and peace defines her character.