Once home to gangster Al Capone, Chicago was notorious during the 1920s for mob killings such as the St Valentine's Day Massacre. Today, the Windy City is once again battling gang violence.
Last September, the FBI named Chicago as America's murder capital after 500 killings were recorded in 2012. Its murder toll was higher than New York's 419 despite Chicago having only one third of the Big Apple's population.
Some of the killings made national headlines. They included the murder in January 2013 of a high school girl who'd recently taken part in celebrations held in Washington for President Obama's inauguration.
Hadiya Pendleton, 15, was shot dead not far from the President's home in Chicago during a gangland shootout. Michelle Obama attended Pendleton's funeral and President Obama spoke of her during his subsequent State of the Union address.
A few weeks later, Chicago was horrified once more when a six-month-old baby girl died after she was shot five times.
The killing of Jonylah Watkins happened in March during a gangland assassination attempt on her father, and that same month 6-year-old Aliyah Shell was murdered in another drive-by shooting.
Homicides continued throughout the summer, and then in September a gunman opened fire with an assault rifle on a basketball game, wounding a 3-year-old boy and 12 other people.
In November, 18 people were shot in one weekend.
Hillmann shakes his head in disgust at Chicago's death toll and offers his view on what's gone wrong in the city where he was born and raised.
"We have people running around our streets with no regards for life. This (Illinois) is the most anti-gun state right now. If you go to Texas or Oklahoma you'll see 50 per cent of people carrying firearms. And they have little crime. You don't see people running into stores robbing with guns. In Chicago, a bunch of thugs will walk into a store and start shooting into the roof and the walls. And there's no one there to shoot back at them."
Hillmann and I spoke before the passing of a new law that allows Chicagoans to carry concealed guns for the first time. It brings Illinois into line with most other US states but while Hillmann believes the move is a step in the right direction he says it doesn't go far enough and citizens should be allowed to carry weapons openly to deter gun crime.
"You can walk about Texas with a rifle or a shotgun," he says. "What I like about open carry is that if you're a criminal and you think, 'I'm going to rob that gas station right there', and you go in and see two people, and one has a gun on his hip, and the guy behind the register has a shotgun, are you gonna rob that guy?"
Hillmann is a member of the National Rifle Association and has strong views on gun ownership. When he was younger, one of his best friends was murdered by a member of a gang called the Spanish Cobras, and his adopted sister, Katy, was shot in a drive-by shooting some years later, although she survived. He says street-gang turf wars over drugs are the main reason for Chicago's violence.
A decade ago, it appeared gun crime was in decline as the Chicago Police Department reduced gang-related crime with an approach viewed as a model for police forces around the world. But the situation has deteriorated badly because of criminals shooting each other for control of a multimillion-dollar drug trade amidst a heroin epidemic afflicting America's third-largest city.
Chicago is ideally placed for the distribution of drugs across the USA. The Eisenhower Expressway - the city's main east-west artery - has been dubbed Heroin Highway because of the heroin, cocaine and marijuana that floods into the city from Mexico.
Chicago is now home to about 100,000 gangbangers. The main outfits include the Almighty Latin King Nation, aka the Latin Kings, America's largest Hispanic gang that dates back to the 1940s and is viewed as one of the most sophisticated and secretive US gangs. After speaking to Hillmann, I met a Latin King called Jimay Tisquerano who says the violence is mostly down to fighting over street corners to sell drugs.
"Guys are trying to get more territory so they can run the streets more," the 32-year-old says. "And that's how the killing starts. Where I live is the border of three gangs - Latin Kings, Satan Disciples and the 2 2 Boys - so all these guys try to control each other's territory. If they see anyone who looks like a gang member, they shoot him. The killing is random, mostly drive-bys. Two weeks ago, in three days they killed three different guys - 17 to 22 years old."
Tisquerano is still a member of Latin Kings, but no longer active. He joined when he was 14 years old, and quickly learned the Latin Kings' modus operandi.
"The gang is almost like a government. You have the top guy who is a president and it keeps on going down to the soldiers. It's very organised. The next level up from a soldier is an enforcer, then Casincas, followed by Incas. Then it goes up to another section. An enforcer controls soldiers in a section of 10 up to 30 guys. Enforcers take orders from Casincas and Incas."
Tisquerano rose from rank and file to become an Inca before deciding to cease gang activity a few years ago, after the birth of his child. During service with the Latin Kings, he survived a gangland shooting but many of his friends were not so lucky. He wears a tattoo on his upper arm in honour of his 18-year-old cousin Williams who was murdered in 2010, and his brother Marcos - also a Latin King - is blind after being shot in the face.
Tisquerano says Illinois' new gun law is unlikely to stem the killing because gang culture is endemic.
It's an opinion I hear later from another gangbanger with the Black P Stones. The Stones are one of the Latin Kings' rivals and have about 30,000 members.
In the suburb of Maywood on the city's west side, I interviewed an ex-con called Anthony, better known on the streets by his nickname, Chopper, an allusion to his role in cutting illegal drugs before distribution.
Formed in the 1950s, the Stones have a historical association with Islam, although there seems little appetite for peace among its membership. Choppers says he joined the Stones aged 10 to follow in his father's footsteps.
"Back then you had to have permission from your parents to become a Stone. You had to go through an initiation and all that. We have seven laws that must not be broken. The Government got laws and we got laws. Our laws teach you how to talk and speak and how to carry yourself around people, basically how to live your life. Once you join the gang you have to be prepared to lose your life and go to jail."
Chopper has been shot twice and has served time in Illinois's infamous Cook County Jail.
He says Chicago's latest problems are a result of gang discipline breaking down and the rise of a new generation of gangbangers who are completely out of control.
"All the structure in the gangs is gone, so there is no leadership. There is so much shooting going on, nobody knows where to turn. It ain't the older guys, it's the young guys, as young as 13. It wasn't like that in the 80s or 90s. This is new. Some of these guys just shoot for fun."
