The searing images of thousands of New Orleans residents, stranded by floodwaters because they had no means to evacuate Hurricane Katrina, have exposed an abiding truth about poverty in America.

Despite more than 35 years of solid economic growth and income gains, the nation’s poverty rate is no better than it was in 1968, just four years after President Johnson launched a war on poverty.

With poverty in hurricane-stricken areas approaching 30 percent _ higher among African Americans _ political leaders of many stripes have issued urgent calls for the nation to do something about the 37 million Americans who fall into the category of have-nots.

“We do, I think, at some point need to see that people couldn’t evacuate who were poor,” said Secretary of State Condoleezza Rice, “and understand better how to make sure that that doesn’t happen again.”

Former Democratic Sen. John Edwards of North Carolina called for a revival of Depression-era public works programs to prop up Gulf Coast residents now homeless and jobless.

But making progress against American poverty constitutes a massive challenge. The nation’s poverty rate is the worst, by many calculations, in the developed world. It’s been growing for four straight years. Blacks and other minorities suffer at much higher rates.

Yet the United States’ poverty picture is more complex than that. After worsening during the 1980s and early 1990s, poverty dramatically improved during the late 1990s _ especially among minority groups and in some of the country’s poorest neighborhoods.

Here are more questions and answers about the poverty picture in the United States:

Q: Some commentators say that Americans have taken their eyes off the problem of poverty in the United States. Has poverty gotten worse in the last few years?

A: American poverty has indeed increased somewhat since 2000, trending up each of the last four years. Experts say some uptick was to be expected as a result of the 2001 recession, though a few were surprised that the increase continued in 2004. Over the last decade, however, the story is a much brighter one. Poverty rates declined sharply in the mid- to late 1990s, approaching the lowest levels on record. As a result, the 2004 poverty rate of 12.7 percent is still one of the best in the last quarter-century.

Q: Why the progress in the 1990s?

A: Experts say the long economic expansion is the overwhelming cause. Many also credit welfare reform legislation that instituted tougher work requirements.

Q: What about a longer perspective? As one of the world’s most prosperous countries, hasn’t the United States gone a long way toward eradicating poverty?

A: Yes and no. There indeed has been progress since 1959, the first year the Census Bureau compiled poverty figures. Then the poverty rate was 22.4 percent, almost double today’s number. But after President Lyndon Johnson began the War on Poverty in 1964 (during a decade of rapid economic growth), the poverty rate plummeted, reaching an all-time low of 11.1 percent in 1973. Unfortunately, the nation has not sustained, let alone improved upon, the low poverty levels of the 1970s.

Q: The plight of African Americans in New Orleans has seemed especially dire. Has minority poverty worsened in recent years?

A: The poverty outlook for African Americans, Asian Americans and Hispanics has actually been a significant success story in the last decade. Even with the recent upward drift, poverty rates since 1993 have declined 25 percent for blacks and Hispanics and more than one-third for Asians. Of course, especially for African Americans, those gains are measured against horrifically high poverty rates throughout most of the 20th century. According to the Census Bureau, 55 percent of blacks were below the poverty line in 1959.

Q: What about the really deep poverty that exists in some of the big cities like New Orleans?

A: The picture here also is one of significant gains during the 1990s. According to a study by Paul Jargowsky of the Center on Urban and Metropolitan Policy, the number of Americans living in high-poverty neighborhoods declined 24 percent during the decade. The biggest progress occurred in some of the biggest bastions of poverty in the Midwest and South _ places like Detroit, Chicago, San Antonio and Houston. (New Orleans had a 35 percent decline in high-poverty neighborhoods, according to the study.) Even so, as a result of rapid increases in high-poverty concentrations in the 1970s and 1980s, the number of neighborhoods with severe poverty remains sharply higher than in 1970.

Q: How does the United States stack up against other developed nations?

A: Not very well. In a recent study by the United Nations, the United States ranked last among 26 countries in the share of population below 50 percent of median income. Among countries scoring better than the United States were Slovakia, Hungary, Poland, Slovenia and the Czech Republic. Rates in 14 European countries were less than half that of the United States’.

Q: Can’t the United States do better than that?

A: Some believe so. Isabel Sawhill, a scholar at the Brookings Institution, says the inability of the United States to lower its poverty rate over 25 years’ worth of solid economic growth raises a question: “Why aren’t Americans more compassionate?” But Douglas Besharov, a scholar at the American Enterprise Institute, says American poverty is not so much a matter of neglect as it is a purposeful decision to concentrate more on faster economic growth and lower rates of unemployment _ at the expense of higher poverty. “I think what you’re seeing now in Europe, with very slow economic growth, is an understanding that their big welfare systems extract too high a price.”