Liverpool mayor Steve Rotheram says middle-class drug users need to realise they are fuelling the violence which claims the lives of youngsters like Olivia Pratt-Korbel.
The 9-year-old was killed by a masked gunman after a gangland feud spilled into her home last month.
Her mother had opened the door to investigate a commotion outside when the killer's intended victim burst in, and his pursuer followed, letting off shots at random.
A major police manhunt is underway and has seen a series of arrests, but the city's metro mayor says the organised criminals responsible have been emboldened by a thriving drugs trade.
"It's one of those moments in life where you just can't believe what you're hearing and watching on telly. It was 15 years almost to the day since Rhys Jones was killed on the streets of Liverpool, and Olivia was in her own home, the safest place she could possibly be," he said.
Nine suspects have been arrested and bailed but, five weeks after the killing, no-one has yet been charged with the schoolgirl's murder. Crimestoppers has issued a £200,000 reward to help catch the culprit.
Speaking on the Mirror's News Agenda broadcast, Rotheram said such violence could often be traced to gangland battles over the right to control the drugs trade. While government needed to do more to tackle the problems, he said well-paid recreational drug users needed to stop and think about how they were funding the violence.
"Some people think, you know, it doesn't really affect them because it's somewhere else. Well, it affects everybody. It's almost like the drugs wars we see, right the way across the country, and people thinking 'the drugs wars, oh that's really terrible', but then go and sniff a line of coke in a toilet somewhere and think that's nothing to do with the violence that ensues," he said.
"They are absolutely part of the problem.This casualisation of cocaine, certainly in middle class circles, is part of the problem for me... it's a societal problem and we need a government to really tackle it, across the multiplexity of all these issues."
While Labour leader Keir Starmer has been criticised for failing to visit striking dockers at the Port of Liverpool during party conference, Rotheram revealed he and fellow metro mayor Andy Burnham would do so, "to give them the belief they're being supported, that the party is behind them".
He said Keir "obviously believes that's the right thing to do" but "he perhaps then shouldn't have stopped shadow cabinet members from going on the picket lines, and he could have been represented".
He added: "I think, if he can't do it, then someone else might go down and show a bit of solidarity."
