Alexander Trampert shook his head as he stared at the smashed windows of the Budnikowsky drug store and the scattered debris inside.
The streets all around him were strewn with broken glass and the charred remains of a makeshift barricade. Several other shops in this neighbourhood in central Hamburg had been looted as well and as residents came out to survey the damage, many were furious at the government's decision to host the Group of 20 summit here.
"We expected something but we didn't expect this," said Mr. Trampert, a sales manager who lives nearby. "I mean, we are somehow used to minor riots, a fire on the street doesn't bother anybody here. But, I mean, this dimension? Come on."
When Angela Merkel selected Hamburg as the site of the 2017 G20 summit, the German chancellor hoped to showcase her birthplace as a beacon of free speech and democracy. She took pains to meet with protest groups before the summit, hoping to head off any extremist activity and ensure that the voices of dissent were heard.
But by the time world leaders departed on Saturday, this city was reeling from days of violent clashes that left more than 400 police officers injured, around 400 protesters in jail, and caused untold damage to businesses and homes. And with little accomplished at the G20 meeting itself, many people here are now questioning the value of these summits.
"We wasted so much money on this G20," said university student Yassin Mabob as he peered into a broken storefront window. "When we compare it with what they achieved? Nothing at all. Why should this foolishness continue? We don't get it. We don't get it at all."
He and others condemned the government's decision to hold the G20 at a trade centre in the heart of Hamburg, only a 20-minute walk from the city's Schanze district, a well-known hotbed for radical groups. Indeed, the epicentre of the anti-G20 movement was the Rote Flora, or Red Flower, an old theatre in Schanze that has long been associated with the squatter movement and far-left causes.
This is where tens of thousands of protesters gathered during the summit and on Sunday, the streets around the theatre were lined with damaged buildings and looted stores. In the nearby districts of St. Pauli and upscale Altona, protesters burned cars and set up barricades. About 15,000 police officers had been brought in to control the protests but officials had to call in 200 more as the violence escalated.
Protests and demonstrations are hardly rare in Hamburg, a wealthy port city with deep working-class roots and a history of leftist sympathies. Attempts to develop vacant property in Schanze and St. Pauli have been met with riots over the years and there were plenty of indications things could turn ugly during the G20.
A gathering in the city's fish market the day before the summit was dubbed "Welcome to Hell" and featured a giant inflated "black bloc," the symbol of groups loosely linked to anarchists. When tens of thousands of protesters began marching toward the summit site, they were met by hundreds of police officers. Within minutes, clashes broke out and the police spent the rest of the day, and night, in running battles with protesters across the city. That became the pattern for the next three days and things became so chaotic at times official motorcades had to be diverted and some events for leaders' spouses were scaled back because of security concerns.
At one point on Thursday, television images showed the surreal scene of G20 leaders listening to Beethoven's Ode to Joy at the city's new Elbphilharmonie concert hall while police used water cannons on protesters outside.
"This was organized and long-prepared criminal violence as we have never witnessed it before," city official Andy Grote told reporters.
Ms. Merkel defended her decision to host the meeting in Hamburg, saying G20 summits had been held in other large cities, such as London and Toronto, and that Hamburg could not have "shirked responsibility." But her foreign minister, Sigmar Gabriel, suggested that all future G20s should be held in New York, the headquarters of the United Nations.
Some politicians were quick to condemn the decision to locate the meeting in Hamburg and police described the protests as a "new dimension" of violence. "The G20 summit should never have been held in a city … like Hamburg – the security situation is too hard to control," said Hans-Peter Uhl, a politician in Ms. Merkel's centre-right coalition.
But many others said the protests shouldn't deter countries from hosting the G20, which they added was an important occasion for world leaders to meet. The G20 is "absolutely" still relevant, said John Kirton, co-director of the G20 Research Group at the University of Toronto. "It's getting more effective summit by summit."
Prime Minister Justin Trudeau said the G20 serves an important role in pushing leaders to find solutions and prove they are listening to the concerns raised by protesters. "Yes, people are anxious and, yes, people are angry," Mr. Trudeau told reporters after the summit. "I understand the skepticism and even frustration of people who see these meetings come and go without watching their benefits or their opportunities increase. And what's more, people around the table are aware of that as well."
He called the Hamburg summit a success even though there were disagreements between 19 countries and the United States over trade and climate change. Mr. Trudeau cited the Paris climate accord as one example and said, "The fact that the G20 stayed strong and committed [to the accord], even with the United States stepping aside, is a strong indication that the global community in general is committed and united."
That won't do much for some store owners in Schanze who spent the weekend cleaning up what was left of their businesses. "G20 is bad," said the owner of Rewe City, a grocery store that had been completely ransacked by looters and partly destroyed. "It's all damaged," he said, declining to give his name. As he sorted through the mess, Malte Newmann watched him from the street.
"I think it's good they had the G20 here," said Mr. Newmann, an advertising manager who lives in the Schanze. The G20 leaders shouldn't hide away in remote locations and avoid the consequences of their decisions, he added. "Do it where it happens and see what happens," he said. "So everybody sees the real emotions which are behind this."