To many Americans, the war on poverty declared 50 years ago by President Lyndon B. Johnson has largely failed. The poverty rate has fallen only to 15 percent from 19 percent in two generations, and 46 million Americans live in households where the government considers their income scarcely adequate. Half a century after Mr. Johnson's now-famed State of the Union address, the debate over the government's role in creating opportunity and ending deprivation has flared anew, with inequality as acute as it was in the Roaring Twenties and the ranks of the poor and near-poor at record highs. High rates of poverty ... have remained a remarkably persistent feature of American society. About four in 10 black children live in poverty; for Hispanic children, that figure is about three in 10. According to one recent study, as of mid-2011, in any given month, 1.7 million households were living on cash income of less than $2 a person a day, with the prevalence of the kind of deep poverty commonly associated with developing nations increasing since the mid-1990s. The 1996 Clinton-era welfare overhaul drastically cut the cash assistance available to needy families, often ones headed by single mothers. Over the last 30 years, growth has generally failed to translate into income gains for workers - even as the American labor force has become better educated and more skilled.