The murder of U.S. Rep. Danny Davis’ 15-year-old grandson over a pair of gym shoes has united black elected officials in a way not seen in decades to combat the entrenched poverty that’s fueling Chicago violence.

On Monday, dozens of African-American politicians came together to demand that at least 10 percent of city, county, state and federal funds be spent in neighborhoods where at least 20 percent of the population has lived below the poverty line for the past 30 years.

In Chicago, that would be “nine or 10 endangered communities,” including Englewood, Austin and West Garfield Park.

At a City Hall news conference, Davis noted that the so-called 10/20/30 amendment is already in place in a handful of federal agencies, including the U.S. Departments of Agriculture, Commerce and Justice.

“Just suppose that the state of Illinois was doing that. Just suppose that the county of Cook, the city of Chicago, that the Water Reclamation District [was doing it]. You would have resources coming directly to communities that are most in need and the impact would be so great, you’d wonder if you weren’t in heaven,” Davis said.

County Commissioner Richard Boykin said “unemployment levels not seen since the Great Depression” are the driving force behind the 50 percent surge in homicides and shootings that has triggered more than 700 murders so far this year.

“Poverty is the worst form of weapon of mass destruction. . . . These communities have been disinvested in intentionally — and it’s been over decades of disinvestment,” said Boykin, who plans to introduce the 10 percent spending mandate to the County Board.

“Much like we sought out to have the will to re-do the South Loop [and] the West Loop, we can seek to . . . re-do communities that have lost hundreds of thousands of jobs to Mexico, to China and other places. And we must do that.”

The Rev. Jesse Jackson called for a White House conference on inner-city violence before President Barack Obama leaves office, culminating in a Great Society-style rebuilding program with Chicago as the guinea pig.

Without mentioning Mayor Rahm Emanuel by name, Jackson took a veiled shot at a mayor who has spent his second term trying to rebuild forgotten inner-city neighborhoods and win back the support of African-American voters who elected and re-elected him.

“A hundred-thousand vacant homes and abandoned lots was not caused by black officials. Closing 50 public schools and laying off 5,000 teachers. When those schools went down, the housing and poverty rate went [up]. . . . Neighborhood grocery stores and cleaners went down with them,” Jackson said.

“The net growth of jobs [is] in the suburbs where our transportation does not reach. That’s why it needs to be a White House conference using Chicago as a model for urban reconstruction.”

Facing deep distrust among black voters who believe their unsafe neighborhoods have been left behind, Emanuel last spring hired former Chicago Urban League President Andrea Zopp to serve as a $185,004-a-year deputy mayor and chief neighborhood development officer.

The mayor has also proposed a steady stream of incentive programs aimed at boosting minority contracting and employment and a $100 million Catalyst Fund to bridge the funding gap outside Chicago’s gleaming downtown area.

Ald. Roderick Sawyer (6th), chairman of the City Council’s Black Caucus, was asked what more he expects the mayor to do.

“The mayor has made some efforts recently in trying to make some additional investments in the South and West Sides. He’s made it very clear that he has every intention of making that mass investment. But it’s to us — all of us here — to make sure that all of this happens,” Sawyer said.

“I respect what the mayor has been trying to do, but we need to be the driving force in all of this. It’s not a top-down approach.”

Javon Wilson, Davis’ 15-year-old grandson, was fatally shot in his Englewood home on Nov. 18 after what authorities said was a senseless argument over a borrowed pair of gym shoes that might have ended in a fistfight, if not for the easy access to guns and a violent movie and video game culture that has almost anesthetized young people to violence.

Last week, 16-year-old Tariq Harris and 17-year-old Dijae Banks were both charged as adults with first-degree murder in Javon’s death after turning themselves in.

On Monday, Sawyer was asked whether the shortage of African-Americans working — either as government contractors or employees — in so many South and West Side neighborhoods was a “collective failure” by black elected officials.

“I’ll acknowledge that we need to do better. . . . If you want me to take responsibility, I will,” Sawyer said.

“What we’ve been trying to do lately is trying to push that envelope — whether it be at the airport, whether it be at CDOT or Streets and San. . . . We put it out there that the numbers aren’t good enough.”

A still grieving but remarkably poised Davis was in no mood to accept responsibility, citing decades of oppression.

“We’re not just talking about last month. We’re talking about from the slave ships. We’re talking about Jim Crow. We’re talking about the remnants of all that has been done to prevent this group of people from experiencing equity. You can’t deny that. You can’t take that away,” Davis said.

“What we have here is a resolve to give out before we give up. The fight has been going on time and time and time and time again.”

State Sen. Kwame Raoul, D-Chicago, said the intense focus on black-on-black crime ignores the “inextricable link between poverty and violence.”

“We must invest in these communities to eradicate poverty and, in eradicating poverty, we will eradicate violence,” Raoul said.

But Raoul warned that any solution on the state level must also address the “trauma” experienced by young people who have seen their relatives and friends gunned down at such young ages that their own lives lose hope and meaning.