Donald Trump wants to build a wall. Scott Morrison claims to be one: the “brick wall” standing between Australians and those who would game our country’s immigration system.

That is how the prime minister characterised himself on Wednesday. He stood, backed by sombre people dressed in uniforms of army camouflage and Border Force black, before a small contingent of media on Christmas Island.

All had been flown there at taxpayers’ expense to see the detention centre, reopened in order to subvert the intent of the so-called medivac legislation passed by parliament in February.

Besides the allusion to himself as a wall, nothing about Morrison’s media stunt was new. He rehashed familiar talking points – his government is strong on border security; Labor is weak, and the last time it was in government, 50,000 asylum seekers arrived in boats.

No one among the media contingent questioned Morrison’s claim to have secured Australia’s borders. In reality, more asylum seekers are turning up under his government’s watch than ever did under Labor. And these people are rapidly becoming an underclass of cheap, exploited labour, hidden from view on farms, on construction sites and in the restaurants and other businesses across Australia.

More than 64,000 people have claimed asylum in Australia over the past three years.

In the most recent financial year alone, 27,931 applications for protection visas were made. That figure eclipsed the biggest year of arrivals under the previous Labor government – 26,845 in 2012–13.

And the number of asylum seekers continues to grow. In just six months, up to the end of January this year, there were another 14,231 applications made.

The people coming now, however, are not coming by boat. Instead, they are flying over the Great Wall of Morrison and landing at Australia’s airports.

Most of those who arrived by boat in the Labor years were determined to have genuine claim to refugee status. That is, they were assessed as having a well-founded fear of being persecuted for reasons of their race, religion, nationality, political opinion or membership of a particular social group, and thus could not return home because this would expose them to a risk of imprisonment, torture or death. We sent them into offshore detention.

Few of those among the current class of asylum claimants are ultimately determined to be genuine refugees. In the case of those coming from Malaysia, the rejection rate is 98 per cent.

However, the design of Australia’s asylum-seeker processing system means these people are not held in detention – onshore or offshore – as are those who arrived by boat. Instead, tens of thousands of people have received bridging visas while their applications for protection are assessed. Eventually, many of them disappear into the community.

While most of Australia’s 1.4 million foreigners with work rights are here legitimately, a large and rapidly growing number are not. As Department of Immigration and Border Security chief Mike Pezzullo recently told senate estimates, 90 per cent of the new wave of asylum applicants have no legitimate claim – meaning as many 50,000 are here illegitimately.

Instead, these people are part of a backlog of some 200,000 visa applicants in the Australian community whose status is yet to be determined. In some cases, this determination process has stretched out for as long as eight years. In June 2017, there were also a further 63,000 “unlawful noncitizens”, which is what bureaucrats label those who have no valid visa at all.

In February, Australian Border Force issued a press release about raids across three states, undertaken as part of Operation Battenrun. “A national operation targeting foreign nationals acting as unscrupulous labour hire intermediaries facilitating illegal foreign work,” it read.

The release focused on one “particularly concerning case” in which five people, including a 16-year-old boy, were found sleeping on mattresses in the garage of a property in the regional Victorian town of Robinvale. A dozen more people were inside the house.

The release quoted the ABF commander of field operations, James Copeman, decrying the “deceitful and immoral labour hire intermediaries operating in the agricultural sector” in the area.

In all, 23 “unlawful non-citizens” were busted. Among them were seven Malaysian men and one man from Hong Kong, all “suspected of being involved in facilitating illegal foreign workers in Victoria”.

“One is further suspected of acting as an illegal migration agent across several Australian States,” the release said.

The raids exposed only the tip of the underclass worker iceberg.

As Emma Germano, vice-president of the Victorian Farmers Federation, says, the Border Force raids in north-west Victoria “essentially shut down” much of the Sunraysia district’s horticulture industry for a week because the workforce went into hiding until they were sure the authorities were gone.

Germano is remarkably frank about the industry’s reliance on illegal labour.

“We’ve done a survey up in the Sunraysia district. Of 65 growers we’ve interviewed so far only one or two have said they are fully compliant [with laws prohibiting the use of undocumented labour],” she says. “People are saying about 50 per cent of the harvest labour is undocumented.”

Furthermore, says Germano, the sporadic enforcement action of border force “seems very much like public relations by government. It makes it look like they are doing something”.

“A number of MPs have admitted to me they’re not trying to clean it up in any serious way, because they know [that without the pool of labour] the whole industry would be in trouble.”

She points out that the same phenomenon exists, less obviously, in other industries.

But, as Tim Nelthorpe, the organiser of the National Union of Workers’ fresh foods campaign, says, reliance on illegal labour has become “the model of employment in that industry”.

The union blames the big supermarkets for “building into their pricing structure a system that leaves the employment of a large number of workers completely unregulated”.

Surprisingly, both the union and the farmers are united in pushing for an amnesty for the current workers and a new agriculture visa to legitimise foreign farm workers.

That might clean up one industry. But the problem is much bigger than that.

It’s getting bigger quickly, says Abul Rizvi, a former deputy secretary of the immigration department.

But neither the government nor the bureaucracy wants to bite into the “shit sandwich”, as Rizvi describes it, just before a tough election.

Instead, Morrison and his government work to stir fear about the consequences of humane treatment of a couple of thousand mostly genuine refugees held offshore. Most recently, the PM pointed to 57 men held on Manus Island and Nauru who may be criminals or have terrorist sympathies.

Yet critics say the growing number of unprocessed asylum claims poses greater concerns for national security and threatens to see the establishment of a permanent underclass of people of foreign origin, exploited by criminal organisations.

The leaders of the government and its bureaucrats deny this. In senate estimates on February 18, Labor senator Louise Pratt asked Mike Pezzullo whether “criminal syndicates or people smugglers” were taking advantage of the visa processing backlog in his department.

“No,” said Pezzullo.

But others, including members of the government itself, say otherwise. At the same time, parliament’s joint standing committee on migration contradicted him, saying in a report that “loopholes in the law are allowing organised crime and illegitimate labour hire companies to exploit Australia’s immigration system”.

These organised criminal enterprises, the committee said, were taking advantage of the long delays in processing onshore claims for asylum, to “bring out illegal workers who are often vulnerable and open to exploitation”. The “orchestrated scam”, as the report called it, involved dodgy asylum claims from citizens of a number of countries, particularly Malaysia.

“The number of permanent protection visa applications lodged by Malaysian nationals over the past three years has nearly doubled,” it noted.

Committee chair Jason Wood – a Liberal and former Victorian police officer who served in the organised crime squad and in counterterrorism – tells The Saturday Paper he was shocked at the extent of the scam.

“It’s just grown and grown and grown over the past few years,” he says.

But where his committee blamed “loopholes” in the law that allow a protracted process of merits review – through the department, the minister, the Administrative Appeals Tribunal, Federal Court and even the High Court – evidence suggests the problem is less about process than resourcing.

Much of the issue goes back four years to a bureaucratic restructuring initiated by Morrison when he was immigration minister, says Rizvi.

“I believe the change started with the marriage of customs and immigration,” he says.

“The Border Force function – essentially the people with the uniforms and guns – got a higher priority than the public servants at desks, who process visas in the first place.

“Two things happened: morale declined among visa processing staff and we had less resources, relative to the number of applications. So, processing times blew out.”

That had an impact on visas of all types. In response, says Rizvi, more people began coming into the country as visitors and applying onshore. This applied to spouses, business-sponsored migrants and, particularly asylum seekers.

“So, the offshore backlog has become an onshore backlog.

“About five years ago, the backlog of bridging visas – which is what the department gives you when they can’t process your application quickly enough – was around 100,000. Now it’s close to 200,000.

“Once the people smugglers saw that paralysis onshore, they spotted an opportunity,” he says.

“What was in the first instance a bureaucratic problem is becoming a national security problem, in that the vast majority of these people entered Australia on a visitor visa.”

In such cases, Rizvi says, only limited background checks are done.

“We now have a very large number of people who have entered Australia essentially on the basis of telling us they have no criminal record, and we believe them.

“The second, probably more important point, is for 30 to 40 years we in Australia have avoided the problems that have plagued countries in Europe and North America, which is the creation of a large, permanent underclass of failed asylum seekers in the country.

“What has happened in the last three years is unprecedented,” Rizvi says. “If the government doesn’t act quickly, the problem will just keep growing, and eventually reach a point where, similar to the US and Europe, you just can’t do anything about it.”