Sen. Joseph R. Biden Jr. (D-Del.) yesterday proposed a $7 billion a year federal attack on poverty among children, arguing that the plan is "phenomenally different" from the Great Society-era Democratic spending proposals but protects the needy from the "hypocritical and hateful" neglect of conservatives.

In a policy address delivered five days before he will formally declare for the 1988 Democratic presidential nomination, Biden blasted as "morally abhorrent" the conservative view that "the real answer for the poor is less government help, not more."

He added, however, that "government subsidy is not the ultimate answer." He called instead for investing in health and education programs that were "proven winners" and that have a good prospect of achieving broad political support.

Specifically, Biden called for the federal government to pay for the health care of every child under age 12 who is living in poverty. He called for an expansion of the Head Start program for preschool children and the Women, Infants and Children (WIC) supplemental feeding programs. He urged more drug treatment and education programs, lenghthening the school day and school year, stiffening curriculum standards and teaching values in school. He proposed paying differentials to teachers in ghetto schools and creating a National Community Service Corps that would enable volunteers to work in poor communities.

"The American people are hungering to join in a new effort," Biden said. "For too long we have celebrated untrammeled individualism in America. For a decade led by Ronald Reagan, we have valued not the valiant but the victors, not the worthy but the winners."

Biden noted, in response to a question, that his program did not include such Great Society approaches as massive public employment programs. "We know they don't work very well," he said, adding that he also rejects proposals for national health insurance.

The speech was the third major address -- the others were on foreign policy and the economy -- that Biden has given in the weeks before his presidential announcement. Biden actually delivered the poverty address two weeks ago in Princeton, N.J., but his campaign staff felt it did not draw enough press attention so Biden gave it again at American University yesterday.

Like the poverty lecture, the foreign policy and economy speeches were built around the search for a pragmatic middle ground between what Biden views as the "inflexible ideologies" of the right and left.

In his foreign policy speech

at Harvard last week, Biden, a member of the Senate Foreign Relations Committee, said "both interventionism and isolationism are defeatist . . . . The Reagan doctrine assumes that change only comes through force. It reduces the struggle between freedom and tyranny to the exchange of fire: AK47s versus M16s . . . . But . . . we cannot insulate ourselves in a protective cocoon."

Biden proposed updating President John F. Kennedy's 1961 inaugural statement to read, "While we cannot pay any price and bear any burden, we must pay the right price and bear the right burden." Biden outlined a three-part test of whether the United States should project force abroad: are vital interests at stake, will the commitment promote American values, and does it have a high probability of success?

In a two-part economics lecture delivered earlier last month at the University of Pennsylvania, Biden set up a similar dichotomy between free traders and protectionists.

He said free traders "believe we can do nothing to change our economic fate" and protectionists "are peddling a remedy to voters they know cannot work."

Instead, Biden said a president must jawbone trading partners to lower barriers, retaliate with tariffs when they do not, and provide more relief to workers and industries dislocated by unfair trade practices.

Biden gave the poverty address the day after a Washington Post-ABC News poll was published showing he, at 3 percent of Democrats polled, is running last among seven active Democratic candidates for the nomination.

"Today, I'm flattered that anyone would show up anywhere to listen to me," he joked to about 150 students who came to hear him.