No past US secretary of state has lived in the White House, but none before Hillary Clinton had been married to a president. She is the only first lady to have run for elected office, winning one of the two Senate seats for New York State in 2000. The win demonstrated her resilience - she had been pilloried by the US right - and her formidable campaigning effectiveness. She might even have been president, were it not for Barack Obama. Clinton campaigned against Obama on the grounds that her greater experience would be required, should world security be in peril. So the new president shrewdly put her in charge of managing global imperilment at the state department. Clinton has unusual autonomy and unarguable authority - in contrast to Obama, who is bogged down in domestic political bickering.
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