Asaad Matoori is 30, and he makes light of it all. He's in a barber's shop, undergoing a male beautification ritual, Baghdad style. "I'm getting ready to fight ISIS," he says, using one of several acronyms for the forces of the so-called Islamic State, now closing on the Iraqi capital.

Matoori is a Shiite from the southern port city of Basra who has signed on for training as a volunteer to fight alongside the Iraqi Army. The paste is a conventional face scrub; and the flaming paper "pencil" in his ear is a local procedure by which heat is transferred to his inner ear and the other end of the paper soaks up any melted earwax.

With all the bravado that befits the barber's chair, Matoori hectors the jihadists who already occupy swathes of western and northern Iraq along with chunks of neighbouring Syria: "We'll break their noses. They can only come into Baghdad if we are asleep – or dead."

'See, things are fine'

Even before touching down at Baghdad International Airport we felt the heat.

The air route in from Beirut took us over Anbar, Iraq's sprawling western province, which is on the verge of falling to IS. In what appeared to be an air cover operation for 100 American military "advisers" just inserted into Ramadi, the besieged provincial capital, a US in-flight refuelling tanker flew past us at close quarters, two jet fighters hugging its tail.

Approaching the city from Baghdad airport, traffic was chaotic. We were reduced to a crawl as we passed the now-abandoned hulk of the Hamra Hotel where, in January 2010, I stood on the balcony of my eighth-floor room and watched as a suicide bomber dispatched by IS in one of its earlier guises drove his delivery van laden with explosives at the hotel at breakneck speed, before detonating to peel the facade from the lower floors of the building, killing 16 people, all of them Iraqis, and wounding 33.

Four years on, the centre of Baghdad was shut down as a precaution for government officials attending the funeral of an MP –  Ahmed al-Khafaji was one of 25 people killed when a car bomb exploded on Tuesday at a checkpoint on the edge of Kadhimiya, a Shiite neighbourhood.

And as Wednesday rolled into Thursday the violence exploded again – by nightfall, at least 36 were confirmed dead and dozens more injured in a series of bombings and a mortar barrage, all in Shiite communities. "They are making a statement to the Shiites fighting them . . . we can target you in your household," Kareem al-Nouri, a party colleague of Khafaji's, said of the attacks, which were attributed to IS.

But here's the thing – many seem to simply ignore the attacks that have claimed about 400 lives this month, on top of more than 1100 dead in September. The government discourages news reports on the extent of the death toll and officials spent much of the week seeking to discredit a claim by no less a figure than the chairman of the US Joint Chiefs of Staff, Martin Dempsey, that but for nifty intervention by two US Army AH-64 Apache attack helicopters recently, IS attackers might have breached the last  line of defence around Baghdad Airport.

"Had they overrun the Iraqi unit, it was a straight shot to the airport," General Dempsey told a US TV talk show last weekend. "So, we're not going to allow that to happen – we need that airport."

And the more official Baghdad and its denizens claim that the capital is safe, the more IS does to undermine those claims. It is hard to dispute that as thousands of jihadists are consolidating gains just beyond the city's boundaries, a brutal campaign of destabilisation is under way within. Baghdad is a city of sirens and checkpoints, of gunfire and explosions.

Driving down Saadoun Street, we swing past Firdos Square. There, the stump of the plinth from which a bronze of Saddam Hussein was famously toppled - the dictator's right foot remains - prompted a local to observe: "Everyone talks of how safe it was, if not good under Saddam – you were safe if you didn't discuss politics."

Now, it seems, everyone is talking politics – and no one is safe. I'm told that Wednesday evening was "a quiet night". But in predominantly Shiite Karrada, a shopping and commercial strip on a hairpin bend in the Tigris River, the pavements were thick with shoppers. Across town, in Sunni Mansour, the stadium-like roar of shoppers thronging the flash new Mansour Mall was proof enough that the chance of a retail discount can trump the menace of a bomber.

Karrada was a riot of electrifying colour – the lighting in the shops, the brilliant colours of display garments that so many Iraqi women wear under those dour outer layers, street-vendors' food displays and flowers. The air was rich with the aroma of food cooking – rotisserie chicken and lamb and masgoof, butterflied river fish cooked near, but not on, red-hot coals.

A group of women in their 40s were bargain hunting – "see, things are fine", said one. "We're out in the streets." But when asked to direct their gaze to the higher branches of the burnt tree, they fall silent.

Minutes earlier, the street vendor Mohammad Khaddum, 43, had been explaining to me the reverence that his fellow Muslims had for the Virgin Mary, particularly those who wanted to have a child who would regularly go to a church to light a votive candle, when he segued to his lucky break just weeks earlier. When a car bomb had exploded outside his open-fronted stall, he surely would have been among the nine killed and 50 wounded had he not gone home to break the Ramadan fast with his family – "I got lucky," he said.

Dressed all in black, as Shiite men often are, he guided me to the base of a spreading street tree, pointing out its charred trunk before pointing to the upper branches – about 18 or 20 metres off the ground, a singed pair of denim jeans; maybe five metres higher, three shredded pieces of pink fabric. "The clothing of the victims," he said.

If the victims' clothing was thrown so far, it doesn't do to think of what the blast might have done to their bodies.

At this point, Khaddum became the first of a half-dozen or more people I would speak to to qualify his insistent belief that the government could protect the capital from the marauding IS gangs.

First, he said, if the city survived it would be by the grace of God, not the brilliance of the government; and two, if it were to fall it would be because of treasonous elements within. He was giving the new Iraqi government of Prime Minister Haider al-Abadi an even break – it couldn't win, but neither could it lose.

'Do you think the Americans would sacrifice 300 men?'

In the barbershop over the street, at the other side of four lanes of jam-packed, horn-honking traffic, Asaad Matoori emerges from the washroom, face clean and ear flame extinguished, to speak of bravery – the people's, not the military's. "We have to get rid of these extremists – everyone will take up a weapon. Don't be afraid, there's no way they will get into Baghdad."

Why the certainty? "The US has dropped 100 advisers into Anbar province today - do you think they will let it fall? And they have 200 more at Camp Speicher, near Tikrit - do you think the Americans would sacrifice 300 men?"

I point out that Anbar might fall any day now and he retorts no, the local police chief had issued assurances that the central areas of the province were securely in government hands.

Would that be Major-General Ahmed Saddag, who had been killed by a roadside bomb at Ramadi just a few days earlier? "No," Matoori said. "It was his replacement."

There seemed to be general agreement amongst the barber's clients that Iraqis could fix this thing for themselves, save for a quiet muttering of dissent from a man at the end of the bench. "No," he said. "We'll be better off when the Americans come."

On Thursday morning, more deja vu when the address I'm given for a Sunni tribal sheikh turns out to be the same apartment complex, adjacent to the old information ministry, where we sometimes went to interview Baathist regime hacks before the fall of Saddam.

"Well, yes, there's been some changes," said Sheikh Marwan Naji Jbarah al-Juburi, when I mentioned the old occupants of the apartments in inner suburban Salhewa. At age 49, Juburi is the spokesman for one of the biggest tribes in the country.

"We're so big, some say we're a nation," he says of a clan that is spread through the north and south of the country; and while it is predominantly Sunni, a quarter to one-third of its membership is Shiite.

We listen carefully to Juburi, who provides a remarkable inside account of the Sunni tribes' reluctance to support the Baghdad government and of the embrace by some tribes and reluctant tolerance by others of IS, also a Sunni movement.

But first the Juburi credentials – as a tribe, as Sunnis and as Iraqis. They are fighters. The sheikh is fiercely proud of his sister Omaya, aged 41, who died on the frontline, fending off the third IS attack in two weeks before the tribe succumbed to IS threats to slaughter 57 families it had captured from al-Alam, a Juburi stronghold near the central city of Tikrit. He produces photographs of his sister in the trenches, brandishing an assortment of weapons.

But Juburi's sister is not his immediate family's only loss in the fight with IS and other hard-core jihadists. "When my father was kidnapped and killed in 2007, as he returned from the Haj [pilgrimage] in Mecca, it was reported that al-Qaeda in Yemen celebrated; when my uncle was killed in 2011, they celebrated in Afghanistan; my brother also was killed in 2007 and all up, more than 500 members of the Juburi tribe have been killed since 2003."

'We let them in'

When IS recently released a written death threat to prominent tribesmen, it was this particular Juburi sheikh whose name was at the top of the list of targeted individuals – probably because he is fighting a media war. His main weapon was the tribe's own satellite TV channel – but it has been forced off the air by brutal IS attacks on his staff.

The Juburi are Sunnis. It was one of this sheikh's uncles who took delivery of the body of Saddam Hussein after he was hanged by Iraq's new Shiite-dominated government in 2006, and took it to the former ruler's hometown, Tikrit, for burial.

By his reckoning the Juburi are realists – the tribe has fought fiercely with IS, but it remains reluctant to join the Baghdad government's fight against the militants. Instead, it is supporting a campaign by a growing number of the Sunni tribes to appeal for direct US support and boots on the ground.

Last week the Sunni president of Anbar's provincial council appealed to Washington to send ground forces and Juburi said that a council of Sunni tribal leaders in the
coming days would likely make the same call. He expressed a careful optimism about the good intentions of newly appointed Prime Minister Haider al-Abadi. However, he said there was so much bad blood after the divisive rule of Abadi's predecessor, Nouri al-Maliki, that trust could not be restored immediately.

Abadi's moves to tackle corruption and to purge the Shiite-dominated officer corps of the Iraqi Army were good steps, but like the other tribes, the Juburi felt let down by being left to defend their lands without assistance from Baghdad. "They have to come and join our fight," Juburi said of the national army. "We're still waiting – they ignored our advice on how to interrupt supplies to IS as they attacked the Baiji refinery; and as we defended al-Alam, we pleaded for ammunition and weapons and they ignored us."

The sheikh can't bring himself to use the word "surrender". "We let them in," he says of the end of the campaign to save al-Alam.

Juburi is convinced his tribe was left without government support because it was predominantly Sunni. He compares the plight of al-Alam to that of Amerli, just 120 kilometres to the east, saying: "It was a sectarian response by the government – Amerli is Shiite, so the whole world flipped and acted to save it from [IS] assaults."

Juburi warned that in the absence of US ground forces and if the Baghdad government continued to act as it did now, IS would not be defeated. "There has to be a serious deployment of foreign forces, because the Iraqi Army cannot do the job. Even the Shiite militias are stronger – because they have the will to fight.

"This new government still has not done enough to earn the trust of the Sunni tribes," Juburi declared. "We have to see more and stronger action before we can commit – we have 1300 fighters in al-Alam, but we are surrounded 360 degrees by IS."

So goes the war. At a cafe down from the barber's shop I'm told a truth about the death of the MP Ahmed al-Khafaji. Sipping his tea, a local informs me: "No one is sad – even the Shiites are happy that the government is feeling the heat. Maybe they will do something for us now?"

Some things have changed in Baghdad – most parts of the city have power from the government-run grid for as many as 12 hours a day, instead of four or five. Supply remains so erratic that those who can afford to still pay the owners of private generators for electricity.

And some things have not changed – despite it being hugely discredited and its inventor revealed as a fraud, security forces on checkpoints still use a useless explosive-detecting "magic" wand on every passing vehicle. When I cock an eyebrow at one of the officers "wanding" us with one of 6000 devices for which Baghdad paid tens of thousands of dollars each, he snorts in Arabic: "It doesn't work, I know."

Again and again this week, I've been asked to observe how "normal" Baghdad was. And when I demanded to know why Baghdadis wanted to be seen as "normal" when
the forces arrayed against them were so menacing and extraordinarily abnormal, a local friend turned on me.

"We live through it all, through all the bombings. So we just clear the debris, wash away the blood and get on with life. After so many decades of so much violence, maybe 95 per cent of us suffer a form of Stockholm syndrome – we are all kidnap victims.

"We all have supplies of food in our homes; we have weapons; and we're tired of it all – we don't give a s--- any more. The first few suicide bombs were a shock – now they're just ticker-tape reports at the bottom of the TV screen."