WASHINGTON (AFP) - Secretary of State Hillary Clinton on Thursday took issue with critics who say United States (US) global power is waning, arguing in her final public speech in office that America will continue to lead the 21st century.
But on the day before she officially steps down, Mrs Clinton called for the nation's institutions and relationships to be modernised, saying what was needed was "a new architecture for this new world. More Frank Gehry than formal Greek."
"Think of it," she urged an audience at the Council on Foreign Relations think-tank. "Some of his work at first might appear haphazard, but in fact it's highly intentional and sophisticated.
"Where once a few strong columns could hold up the weight of the world, today we need a dynamic mix of materials and structures."
In a strong defence of her four years in office, Mrs Clinton recalled where America was when she took up the post at the start of President Barack Obama's first term in office.
"Remember what we faced in January 2009: Two wars. An economy in free-fall.
Traditional alliances fraying. Our diplomatic standing damaged," Mrs Clinton said.
"And around the world, people questioning America's commitment to core values and our ability to maintain our global leadership.
"That was my inbox on Day One as Secretary of State." Four years on, the world "remains a dangerous and complicated place," but much had changed, Mrs Clinton argued, saying "we've revitalised American diplomacy and strengthened our alliances."
"In short, America today is stronger at home and more respected in the world. Our global leadership is on firmer footing than many predicted."
She stressed Washington needed to use all the levers of global power at its fingertips, widening the "aperture of our engagement." "You can't be a 21st century leader without 21st century tools - not when people organise pro-democracy protests with Twitter, while terrorists spread their hateful ideology online." And she warned perceptions of the US abroad were changing.
"The reservoirs of goodwill that we built around the world during the 20th century will not last forever; in fact in some places, they're already dangerously depleted," Mrs Clinton said.
"New generations of young people do not remember GIs liberating their countries or Americans saving millions of lives from hunger and disease."
As she prepares to hand over the baton to incoming secretary of state John Kerry, Mrs Clinton insisted America would remain "the indispensable nation."
"That's not meant as a boast or an empty slogan - it's a recognition of our role and our responsibilities. That's why the declinists are wrong. And it's why the US will continue to lead in this century, even as we lead in new ways."