Conroy familiarises himself with the NBN at one of the installation sites in Niagara St Armidale, NSW. Credit:Craig Schneider What about doubt? He wants to retort but doesn't, realising he needs to answer. ''When I finished the letter of offer to Telstra, I paused to think, wow, this is big.'' He allows himself one brief backwards glance at that moment, but is soon intolerant of the introspection. ''There have been no nightmares. I believe in this project and I believe in our capacity to deliver it.'' Believe in it Stephen Conroy does. He is architect, designer, chief spruiker - applying a characteristic level of obsession to a scheme that is the largest public infrastructure project to be undertaken in Australia since the Snowy Hydro scheme. He appears possessed by the sense that if he keeps moving fast enough, if he maintains forward momentum, then the knockers won't catch him, he will actually pull this off. But not everyone has Conroy's singular, unremitting belief in the NBN. Others have strong doubts. He faces a formidable political adversary in his opposite number, Malcolm Turnbull.

The critique of the NBN runs on several tracks. It's too expensive. Governments should not pick winners when it comes to technology. Given we inhabit the world of the iPad and the laptop, wireless could well overtake fibre. Productivity benefits can be claimed but they can't yet be proved. There has been insufficient independent scrutiny. Costs will inevitably blow out. There isn't enough skilled labour to deliver the project on time. Aren't we leaching valuable dollars from health and education? Will the government force granny to have the internet when she just wants a phone? Isn't this just a folly, an act of epic socialism in an age in which government is supposed to step back and allow the private sector to do its thing? Day after day the national broadband network finds itself flaming in Canberra's crucible. The criticism from some interest groups and some experts has been so relentless that the tsunami of negativity at times overwhelms the alternative reality: the possibility that such projects can be delivered successfully and they can have transformative benefits. In selling the NBN, the government is burdened by perceptions it cannot manage big programs. Look at insulation. Green loans - what a debacle. The narrative that paints the cabinet as a bunch of incompetent nincompoops blundering around with your money is now so dominant that the government struggles to defend itself on any front. It is true the government's record in program administration is patchy. It is also true it has not been aggressive enough in countering the incompetence narrative when it is overblown. A national school building program with a 3 per cent complaint rate is now considered a ''debacle'' - imagine what could go wrong with the NBN. As one government person puts the conundrum privately: ''Just as well we didn't invent the wheel; we couldn't have sold it.'' Conroy can't be accused of letting negative perceptions drift. He fights every point. If he feels criticism is more about ideology than substance he will say so. He believes for instance that The Australian has campaigned against the NBN. The Murdoch broadsheet prides itself on applying rigorous scrutiny to big government projects, and it has strongly defended the journalistic merit of its stories on the NBN. But Conroy says it is a campaign. ''The Australian has looked for ways to criticise the NBN. I don't believe those criticisms stand up to reasonable scrutiny. I'm happy to take their criticisms head on and make sure Australians have the facts.''

Oddly enough, the most right-wing minister in the government can mount the most cogent case for a big government project such as the NBN. Conroy is not a particularly gifted speaker, he doesn't have flowery rhetoric, his delivery lacks subtlety, he is relentless rather than inspired - but he can make a clear case for his project because he believes in it, he understands his own rationale, he is unafraid of getting caught up in a culture war. He is a genuine enthusiast. ''I'm not going to walk away from where I want to be.'' The implementation of the NBN will make or break the project in the eyes of the public. This is a $27 billion investment. Conroy and the executives at NBN Co, the company building the network, have to get the rollout right, and they know it. Past government failures are heavy lead in the saddlebags. Botching the NBN would pitch the government into terminal political territory. Nailing the NBN would help turn some of the negative perceptions. But it requires patience. The network cannot be produced overnight, and that is risky in a political climate dominated by the instant gratification of the 24-hour news cycle. And while the rollout goes on, technology does not stand still. Conroy grinds his teeth when pressed (as he is almost daily) on the issue of wireless: will mobile networks ultimately prove more popular with consumers at present dumping their landlines? Will the fibre network, the Rolls-Royce, be shunned in favour of a zippy little runabout that gets you there if you aren't sold on the premium offering? Only this week, the government was warned by an advisory firm that competition from wireless technology posed a real risk to the NBN's revenue. The economic case for the NBN relies on an assumption that 70 per cent of households will have signed up by 2025. Demand below that threshold means taxpayers won't see their money back. Is Conroy sure his boffins have got it right? ''Absolutely,'' he says over his shoulder in a car as we drive through Armidale.

The Conroy mantra is fibre is the backbone; wireless and satellite have their place but only fibre is ''infinitely upgradable''. In blunt-instrument mode, he declares: ''The Liberal Party and its cheer squad are trying to convince Australians that they don't need fibre. Wireless will surpass copper but they haven't yet found a limit to the capacity of fibre. There are a range of writers, columnists and shock jocks prosecuting the [you can do it with wireless] argument, but not a technologist in the world will support that.'' But the point is the assumptions underpinning the NBN business case. Is he confident they won't be derailed by strong consumer demand for mobility? Telstra, after all, has just launched 4G mobile technology. ''Only in the CBD and in limited regional areas, without definition of the areas,'' he scoffs. ''We had Goldman Sachs and McKinseys and Ovum look at it - they said our assumptions were reasonable.'' ARMIDALE is a long way from the national capital, high on the tablelands of northern NSW. Conroy has flown in to inspect the rollout and take part in a forum hosted by the University of New England; technicians in fluoro safety gear are sprinkled through the town. The independent-minded folks of Armidale seem bored or perplexed by all the hollering down south. The cafes are not buzzing with philosophical arguments about whether public investment is appropriate - they have just rushed to the NBN. The take-up rate here is 88 per cent. NBN cables are being strung overhead in the established parts of town and trenches are being dug along the footpaths of the new housing developments in order to connect fibre to the home. The rollout is proceeding calmly. There are five ''first release'' sites around the country: Armidale will probably be finished first. Testing of the new network will begin in April.

Lonnie Penrose is overseeing the building work; 50 or so contractors, 4000-plus connections. He is a laconic sort of bloke, keen to show the minister from Canberra that the rose bushes and lawns of Armidale are more or less safe from the intrusions of his contractors. The only trench evidence is a thin line of seeded topsoil in some streets. Rain has helped the strips of lawn regrow. So how are people responding? ''People are welcoming it with open arms,'' Penrose says as he steers his car through a new housing development on a hill overlooking the university campus. No dissent? Penrose thinks that over before volunteering that one lady insisted on having a green box on her house. ''She really wanted a green lid.'' Does the local media coverage reflect the controversy of the national political debate? ''I haven't seen a bad news story in the local paper,'' Penrose says. ''Up here it's just something for the region, something for the bush.'' The men in fluoro would probably rather be getting on with their work than providing the backdrop for Conroy's travelling party, but they chat away amiably. They down tools briefly at the university to accommodate a crew from Four Corners seeking fresh perspective on the story. The crew wants images of Conroy helping to lay down cable. Just down the hill, his cabinet colleague Simon Crean has taken the morning shift. Crean, responsible for regional development, is also in town to help sell the broadband network.

The forum is the baby of independent Tony Windsor, who chose to back Julia Gillard as Prime Minister largely because of the NBN. Armidale is in his electorate and he spruiks the policy as passionately as Conroy. People in the bush want the NBN ''because it negates location and distance'', Windsor says. As far as he is concerned, the rollout needs to be done properly ''and it has to be fibre optic''. Like Conroy, he believes News Ltd newspapers have created a lot of noise about the NBN with excessively critical coverage. ''The rollout will cut through that noise,'' he says. ''As this gets rolled out it will market itself.'' After holding court with local government and local business representatives, Crean stands up for the local TV cameras, relentless on the stump. ''The NBN is fundamental to underpinning the future of this region,'' he says, with Conroy and Windsor looking encouraging on the sidelines. Conroy smiles widely for the cameras. ''Armidale is the best, I love coming to Armidale, the response here is just fantastic,'' he enthuses. Windsor smiles a Delphic smile. Local business people are unsurprisingly keen. Hugh Eastwood, who employs 700 casuals in his Glen Innes photographic business, came along to hear Conroy. ''I'm fully of the view the NBN is the railroad of the 21st century,'' Eastwood says. He does pause at the big price tag, but says the NBN will benefit his business. ''This creates huge opportunity for the decentralisation of services outside the cities.''

Likewise Susan Cull, an Armidale-based exporter. Hers is a science-based company making sensors that measure water in soil. She wants to stay in Armidale for the quality of life, and the NBN will give her scope for online face-to-face consultations with international clients. ''I employ 15 people. I'm hiring 15 more. We are contributing. I'm an exporter, I should have free parking somewhere. I am contributing to Australia's export income.'' Cull is disillusioned by the political debate. The Coalition is just wrong on this, she says. ''We should be building our country on the basis of science. They are uninformed. All this political mumbo jumbo being bandied about: where does the Liberal Party think Australia ends? At the Blue Mountains? I assure you intelligence doesn't stop at the Blue Mountains. The cost of the NBN doesn't bother me at all. What price do you put on Australian intellect? We need to look to the future.''