While progressive trailblazers and feminist groups in the United States are pumping up advocates and activists as the 2012 elections approach, an impressive handful of women — historic first-timers — are forging roles on the international scene as leaders of the new century at this time of economic turmoil.

It seemed emblematic of their global advance that the Nobel Peace Prize was awarded last week to three women from Africa and the Arab world: President Ellen Johnson Sirleaf of Liberia, 72, the first woman elected head of state in Africa; the Liberian activist Leymah Gbowee, 39; and Tawakkol Karman, 32, who ignited the anti-government revolt in Yemen.

In Brazil, President Dilma Rousseff, 63, an economist and onetime Marxist militant, leads the world’s seventh-largest economy.

In her first year as the first woman to run Brazil, it has experienced its highest growth in 25 years.

In the past decade, 30 million Brazilians were lifted out of poverty into the middle class, and the country became one of Washington’s top creditors, nurtured a free-spending consumer society and spawned high-end jobs and ventures that are drawing foreign bankers, investors, law firms and engineers.

Real estate is booming. Rio de Janeiro is now the most expensive city in the Americas, and huge oil reserves have been found offshore.

There are big problems too: inflation, a slowing industrial sector and huge spending on welfare, wages and gigantic projects for the 2014 World Cup and the 2016 Olympic Games.

How will Rousseff manage such a behemoth – the richest, largest, most racially diverse and most hyperbolic nation in South America?

“Rousseff’s got her eye on the future and on the main goal of eliminating poverty and making the country more egalitarian,’’ said Mario Garnero, chairman of Brasilinvest, a private development agency and business bank, and head of the Fa–rum das Americas and the UN Association-Brazil.

“She’s anti-corruption, doesn’t have an anti-American attitude, and she’s putting a strong accent on social and anti-poverty plans while also being pro-business.’’

A prominent entrepreneur, quasi-diplomat and globe-trotting policy consultant who has counted political leaders and popes among his acquaintances, Garnero was in New York recently to preside over a conference on sustainable development, a daylong affair at the Harvard Club with 500 international business and political leaders, including Bill Clinton, who closed the event with a sharp dissection of the economic crisis.

Something of an expert on the levers of power, Garnero ruminated later that week about the women striding the new global stage. Besides Rousseff, he named Secretary of State Hillary Rodham Clinton, Chancellor Angela Merkel of Germany and Christine Lagarde, the new director of the International Monetary Fund.

‘’Hillary projects the image of a new America which understands that power is changing dramatically and that powerhouses need to think in an interdependent world without supremacy, but with the need for dialogue,’’ he said.

Clinton, 63, the first American woman to make a credible run for the Democratic presidential nomination, is currently among the most popular public figures in the US.

She has earned high marks as the top US diplomat and is an indefatigable promoter of women’s rights.

Although she has insisted she will not run again, she is on many a short list of potential presidential candidates in 2016.

As for Lagarde, 55, the first female IMF managing director, “with a strong hand behind a nice smile, she is guiding the IMF to a role of prominence in the great debt restructuration that most countries from the G-7 will face,’’ Garnero explained.

Lagarde took over the IMF after Dominique Strauss-Kahn resigned over a sexual scandal in May in New York.

A free-market supporter, she reportedly favours tight budgets and spending cuts and oversees an institution with 2,500 economists and policy advisers.

Merkel, 57, is the first female chancellor of Germany, Europe’s largest economy, and as such a leader of the fractious European Union. Lately, she has been walking a tightrope, trying to find a way to stabilise the debt crisis, keep the euro zone united and preserve her own seat.

“Will she keep Germany dominant in Europe and her popularity and political coalition afloat?’’ Garnero wondered.

Without the reins of state power but with a large platform, Michelle Bachelet, 60, the first female president of Chile, is now the executive director of UN Women (UN Entity for Gender Equality and the Empowerment of Women).

A lifelong women’s advocate and a former political prisoner under the Augusto Pinochet regime, she has grappled with lack of financial resources at the United Nations, and some expect her to return to Chile to run in the 2013 presidential election.

Recently, however, she was off to Europe, carrying on her mission to empower women.

The list of women with no state power but a large platform would be incomplete without another, Michelle Obama, who is using her White House platform to promote concerns about a human basic: health, and in particular the health that can be gained from eating right and exercising more.

‘’The global impact of women in leadership positions is every bit as exciting as what’s happening on the national stage,’’ said Jessica McIntosh, a spokeswoman for Emily’s List, which fosters female candidates in the United States.

“The more young women and girls can look up to women in power, the more likely they are to see themselves holding such a job.’’

Perhaps US women, having given the world a powerful message of fighting for equality, can now learn in return.

Gbowee, speaking in New York at the InterChurch Centre after learning of her Nobel honour, told the crowd, “The world is upside down, your society is upside down.’’

She criticised the United States as lacking enough drive for social change.

“It’s not enough to be comfortable and say the world’s problems belong to the world,’’ she said.

“One day the world’s problems will meet you at your doorstep.’’