The United States is known as the richest and most powerful country in the world. It could afford to spend more than a trillion US dollars on wars in Iraq and Afghanistan and builds B-2 stealth bombers that cost $2 billion a piece. Yet daily life in its cities often defies such an image.

On my way to and from work via the Washington, D.C. Metro, it's almost always the beggars who greet passengers coming in and out of the stations. They include both men and women, old and young. Some hold signs saying "hungry", "out of work", "homeless" or "homeless veteran".

And outside the Martin Luther King Jr Memorial Library just two blocks from my stop, the Metro Center, there are lines every day of homeless people waiting for free meals distributed by charity organizations or shelter buses coming to pick them up and take them to a place to stay. Although some of the homeless choose to sleep on park benches or some in cardboard boxes in alleyways. On freezing winter days, such as those two weeks ago in Washington and New York, some homeless slept on the sidewalks over the subway grates where the rising heat kept them warm.

Such a picture is true not just in Washington, D.C. and New York, but also for other major US cities, such as San Francisco and Seattle. They are all great cities and my favorite cities in the US, but they would be so much nicer without these scenes, which are surely avoidable in a country as rich as the US.

In his coverage of Camden, New Jersey, last year, NBC anchor Brian Williams described the poorest US city as "staggering poverty surrounded by staggering wealth". The run-down houses in Camden contrast sharply with the glitzy skyscrapers of Philadelphia on the other side of the Delaware River.

Statistics show that 15 percent of Americans, or close to 50 million people, were living in poverty in 2012, according to US Censors figures.

They included a disproportionate number of African Americans and Latinos.

A Pew Center report shows that poverty among African-Americans, although it has fallen slightly over the years, is still 27.2 percent. Meanwhile, the share of Hispanics in poverty has risen over the years to 25.6 percent in 2012. Both are more than double the rate for whites, which is 12.7 percent.

There is no doubt that the poverty in the US is quite different from that in the developing world. Many of the poor in the US may have computers, dishwashers and cars. But the existence of such a large underprivileged group is proof that something has gone seriously wrong in this society.

Americans have been debating this issue in the past weeks as they mark the 50th anniversary of President Lyndon Johnson's War on Poverty. Some have applauded the great achievements that have been made since the 1960s, but others have mocked it, quoting former president Ronald Reagan's quip that "the United States fought a war on poverty and poverty won".

Both views may be true to some extent, but with the poverty seen on the streets, as well as the poverty that is out of sight, it is no wonder Christine Lagarde, managing director of the International Monetary Fund, pointed a finger at the US on Wednesday when she warned that in far too many countries, the benefits of growth are being enjoyed by far too few people. She warned the fact that 95 percent of income gains since 2009 went to the top 1 percent in the US was "not a recipe for stability and sustainability."

It is clear that poverty reduction is not just an urgent task for developing countries such as China, which has lifted 600 million out of poverty in the past few decades and still faces enormous hard work ahead. It is also a pressing one for the richest superpower.

The author, based in Washington DC, is deputy editor of China Daily USA.

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