WASHINGTON – Secretary of State Hillary Rodham Clinton, at times emotional and fierce, insisted on Wednesday that the department is moving swiftly and aggressively to strengthen security at U.S. missions worldwide after the deadly Sept. 11 raid on the consulate in Libya.

In her last formal testimony on Capitol Hill as America's top diplomat — but perhaps not her last time on the political stage — Clinton once again took full responsibility for the department's missteps leading up to an assault at the U.S. facility in Benghazi, Libya, that killed Ambassador Chris Stevens and three other Americans.

Her voice cracking at one point, Clinton said the experience was highly personal.