Hilary Clinton: The most active first lady

Former US Secretary of State Hilary Clinton looks on at Chatham House in central London, October 11, 2013.[Photo/Agencies]

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Hilary Clinton was the first US first lady to hold a postgraduate degree, and had her own career before entering the White House.

The former secretary of state played a key soft power role in US diplomacy.Clinton traveled to 79 countries during the time when her husband Bill was US president from 1992 to 2000, breaking the record previously held by Pat Nixon. During those trips, she often deviated from Bill Clinton's diplomatic team and traveled alone.

"This emphasizes a message, that a country's prosperity is related to the level of education in women and a sense of happiness," says Clinton.