The mayors of Chicago, Washington DC, Kansas City, Portland, Seattle, and Albuquerque, have written a letter saying: “This administration's egregious use of federal force on cities over the objections of local authorities should never happen.”
Although the situation in Portland, Seattle and Washington is mostly derived from political tension stemming from the Black Lives Matter campaign, gun crime has risen markedly in Chicago, Kansas City and Albuquerque.
President Donald Trump has launched Operation LeGend - described as "a sustained, systematic and coordinated law enforcement initiative in which federal law enforcement agencies work in conjunction with state and local law enforcement officials to fight violent crime" - to tackle spikes of violent crime in several cities.
The operation was named after four-year-old LeGend Taliferro, who was shot and killed in Kansas City last month.
Four children - Sincere Gaston, who was 20 months old, three-year-old Mekhi James, Lena Nunez, 10, and Amaria Jones, 13 - died in gun violence in Chicago in June and earlier this month 15 people were wounded after a drive-by shooting at the funeral of Donnie Weathersby, who had been shot dead a week earlier.
Last week, President Trump and Attorney General William Barr signalled their intention to send the FBI, ATF, DEA, US Marshals Service, and Homeland Security agents into Chicago.
Lori Lightfoot, a Democrat and former US Assistant Attorney who was elected Mayor of Chicago last year, told CNN on 26 July: “We can't just allow anyone to come into Chicago, play police in our streets and neighbourhoods when they don't know the first thing about our city. That's a recipe for disaster…I’ve said it before and I’ll say it again, no troops, no agents are coming in outside of our knowledge, notification, and control that are violating people's constitutional rights. That’s the framework."
Peter Cunningham, a spokesman for Chicago CRED (Creating Real Economic Destiny), said: "The president is always looking for someone to blame and a way to divide us politically. Sending in federal troops would be a terrible mistake, which i think he realised and amended it to be federal agents who can support more investigations."
He said Chicago had a very low murder clearance rate, which prompted some people to exercise "street justice."
“Chicago has a very low murder clearance rate and the rate for non-fatal shootings is even lower so anything to boost clearance rates is helpful - as long as it doesn't lead to the kind of illegal crackdowns and abuse that undermined trust in the first place,” concluded Mr Cunningham.
But what is it about Chicago’s gun crime problem that appears so intractable?
Mr Cunningham said the city was surrounded by states like Indiana which had weak gun laws and those weapons end up being used in the city. Six out of 10 guns used in Chicago crimes were bought outside the state of Illinois.
Mr Cunningham said: "There's a long and troubling history of gang culture in Chicago that has defied every effort to contain it. A few decades back, several top gang leaders were imprisoned which unfortunately led to increased violence as in-fighting escalated."
The list of Chicago gangs includes the Gangster Disciples, the Latin Kings, the Vice Lords, the Almighty Black P Stones, the Four Corner Hustlers, the Mickey Cobras and the Two Sixers.
But Mr Cunningham said: “Today there are many unaffiliated street groups with little structure and they seem to have forgotten some of the old rules of engagement that governed gang activity. For example, firing into crowds with innocent people was taboo years ago. Dishonouring the dead was taboo. Today both happen - and social media accelerates it.”
Chicago CRED was created in 2016 with the intention of transitioning youths from the illegal economy - mainly the drugs trade - to well-paid legitimate jobs.
Mr Cunningham said: “These communities have been grossly neglected in the last 50 years. The black population in Chicago is down by a third, the business community has disinvested, and the banks have stopped lending to black homeowners.”
Most of the murders happen on Chicago's South Side, in neighbourhoods such as Englewood where poverty and social deprivation levels are high.
"Most of these young guys never got a first chance in life. We can't arrest our way out of the problem. we have to invest in our young people and give them that first chance they never had,” he urged.
But Trump and many of his supporters do want to "arrest their way out of the problem" and believe the answer is to send in more and more federal agents and possibly even troops.
Mr Cunningham said Chicago’s Police Department had tried numerous initiatives over the years to reduce murders and gun crime - community policing, CCTV cameras, the ShotSpotter audio surveillance system and dedicated gang units, some of whom have since been disbanded.
"Now they are talking about surges but more and more police don't seem to make a difference. We have to provide positive and meaningful alternatives to the young people involved," he added.
He said Chicago CRED’s approach was to use outreach workers to engage directly with the young people most at risk and recruit them into our program by offering them “a paycheck, counselling and therapy.”
They also offer life coaches and support former gang-bangers while they get their high school degree or find a job.
“It doesn't work every time and it doesn't work for everyone, but it's clearly made a difference for some of them and with more resources we could help more people,” Mr Cunningham admitted.
He said the COVID-19 crisis and the Black Lives Matter campaign had both affected the situation in Chicago because they were discouraging police officers from being in contact with people in the most crime-hit neighbourhoods.
Mr Cunningham said: "It’s a little hard to serve and protect if you are staying in your car. The scrutiny on police has paralysed many officers who worry about being the next viral video. Ultimately, they need to be trained to de-escalate and to engage with people to solve neighbourhood problems. It’s about building trust and it's hard to build trust behind a mask and even harder to build trust when people are protesting about the police. But we have to keep trying."
Last month Chicago Police’s Superintendent David Brown urged people to come forward with information to help police catch the "evil, murdering bastards" who killed Sincere Gaston, who was shot dead as he sat in his mother’s car at a traffic light.
Mr Cunningham said: "Sincere Gaston's father Thomas is in our program and he often brought Sincere to our office for meetings so his death hit us even more personally than the other killings we live with every day."
He said: "Our best hope is to invest in more young men like Thomas Gaston - give them a job, give them hope, and a reason to put down the guns even when they are hungry for revenge. We have to help them see that revenge won't bring back (children like) Sincere, but a safe and healthy life for the Gaston family is the best way to honor Sincere's life."