For example, the Spanish conquistadors imposed Spanish rule in South America at the cost of millions of lives lost and more millions enslaved.

In a somewhat similar way, the European invasions of North America and Australia had devastating consequences for the indigenous inhabitants who were variously killed by introduced disease, dispossessed by force or, all too frequently, simply killed.

In trying to fairly assess its impact, whatever good flowed from European imperial expansionism has to be significantly if not entirely offset against the often awful cost in terms of lives ruined or lost, lands seized and wealth stolen.

This is the subject of an ongoing and sometimes very heated debate amongst historians.

PNG was one of the last places to feel the impact of European imperialism and its pacification followed a quite different pattern to that experienced elsewhere.

It is clear that the level of violence inflicted upon Papua New Guineans was less indiscriminate and more controlled than had been the case elsewhere.

From the outset, both in PNG and in the Pacific Islands more broadly, colonial authorities made considerably greater efforts to achieve ‘peaceful penetration’ of the countries they had annexed.

This was a more thoughtful style of administration than had been the case in the past.

I think this reflected a growing view, especially in Britain, that the supposed ‘civilising mission’ of European powers ought to be conducted, where reasonably possible, in a humane and non-violent way.

This type of thinking had firmly gripped the minds of British colonial administrators by the late 19th century and appears to have been very influential amongst those sent to the Pacific Islands.

As well as being a more morally defensible policy, this view was also grounded in hard headed pragmatism: it is much easier and far less costly to govern a country with the tacit consent of the governed than to be engaged in constant guerrilla warfare with dissident elements.

Papua (and later New Guinea) was fortunate enough to have the services of two outstanding colonial administrators, both of whom were adherents to the idea of implementing colonial rule in a moral and non-exploitative way.

The first stroke of luck was the appointment of Sir William McGregor as Papua’s Administrator (1888-95) and later its Lieutenant Governor (1895-98).

McGregor generally avoided the use of violence to impose colonial rule, preferring flattery and persuasion. He was also an accomplished linguist – he spoke fluent Motu - and an energetic explorer who undertook extensive patrol work throughout Papua.

Importantly, it was McGregor who insisted that Papuans not be dispossessed of their land.

Land could only be bought or sold by the Administrator and, usually, this it was only made available to planters as leasehold.

As a consequence, very little Papuan land was permanently alienated from its traditional owners.

This one policy removed at a single stroke one of the greatest potential sources of conflict associated with European colonialism across the world.

Once the fear of land being expropriated was allayed, it became easier to persuade Papuans to abide by the rule of the colonial administration.

Sir Hubert Murray took over as Lieutenant Governor in 1908 and held this position until his death at Samarai in 1940. He was a man of a similar outlook to McGregor and during his long career ensured that the policies established by his predecessor remained in force.

As well as being a distinguished soldier and jurist, Murray was a humane and enlightened administrator.

He sympathised with the Papuans as a people and was determined to protect what we would now describe as their human rights whilst at the same time working energetically to convince them of the merits of the rule of law, good basic hygiene, education and paid work.

While Murray would at times sanction punitive expeditions against persistent criminality, he generally abhorred the use of force believing that it usually led to injustice not redemption.

When New Guinea was brought under Australian control in 1918, these same ideas were implanted in the minds of the patrol officers charged with pacifying the still largely unexplored and uncontrolled Highlands.

Murray established a pattern of thinking and behaviour amongst patrol officers that, with rare exceptions, persisted until PNG’s independence in 1975.

As a consequence, the use of lethal force was always regarded as a last resort and, where it was used, the officers responsible were held accountable for their conduct.

It would be wrong to suggest that this system was perfect. There were examples of excessive force and harm done that was not reported or under-reported.

However, the historic record suggests that extra-judicial killing was rare and certainly not on the scale known to have occurred in Africa, Australia, North America and South East Asia.

While the attitudes and behaviour of the colonial authorities go some way to explaining the mostly peaceful implementation of Pax Australiana, it is not sufficient explanation in itself.

The attitudes of Papua New Guineans towards colonial rule were also a significant factor.

Here, I find myself with few documentary accounts to draw upon. One marvellous source is Captain John Moresby’s Discoveries and Surveys in New Guinea and the D’Entrecasteaux Islands, published in 1876 and a complete record of the voyage of HMS Basilisk largely in New Guinea waters for a month short of four years from 1871-74.

Amongst its many revelations are descriptions of how the coastal people generally responded to outsiders (in brief, maturely and intelligently), and there is a wonderful and unexpected supplementary chapter, ‘Our Duty to New Guinea and Polynesia’.

You can link here to a facsimile of the complete book

The early 'outside men' who explored the Highlands in the 1930s faced a rather different situation.

But even the most aggressive PNG warrior of that era rapidly came to understand that bows, arrows and spears were no match for the rifles and revolvers wielded by patrol officers and police.

The people gained this understanding either from firsthand experience or from the stories of those who had witnessed the results of attacks upon patrols.

I think it is reasonable to suppose that stories of the lethal power of guns would have rapidly spread far and wide.

The use of these powerful weapons was, after all, a very shocking event for people who had no previous concept of the lethal firepower available to the white men who had dared to traverse their traditional lands.

I do not think Papua New Guinean warriors were any less aggressive or brave than their counterparts in Africa or North America.

However I do believe they were better able to make a rational assessment of the situation confronting them and, in most cases, soon decided that attempting to dislodge the invaders by force was not a realistic option.

It also must have been apparent early on that the patrol officers who first contacted them sought to do so in an obviously peaceful way and presented no immediate threat provided they were not attacked.

In particular, they did not seek to seize land or property, nor (at least initially) did they seek to interfere unduly in the normal pattern of life before the patrol moved on.

This would have brought some comfort to people anxious about what the colonial power intended and thus reduced tensions to some degree.

The evidence for this is that the early patrols were frequently able to move across the country without often being threatened or attacked.

My supposition is that people decided to view them as a curiosity at first, preferring to stay back and observe them rather than jump to conclusions about what level of threat they might present.

There is ample film evidence of people, including women and children, mixing with patrol officers and others quite freely after even first contact.

People were often fascinated by things like clothes, tools, mirrors or record players which they found hugely interesting.

The sight and sound of aircraft was a source of wonderment and excitement. There are few indications that people were unduly fearful or anxious.

Then, as the Administration began to impose the rule of law, especially in relation to the suppression of tribal fighting and killing, many people (especially women I think) would have realised that this was, in fact, no bad thing.

The Administration’s action to reduce the risk and fear that had been a permanent feature of peoples’ lives. I find it hard to believe that this behaviour did not soon strike most people as being desirable.

It also rapidly became apparent to people that the Administration brought with it access to desirable goods and services.

This extended beyond material items like clothing, foodstuffs and metal tools to health services, schools, transport and agriculture.

In essence, what I propose is that, once peoples’ fears about the Administration’s basic intentions had been substantially allayed, compliance with its comparatively modest expectations and rules made sense.

Resistance was ridiculous in such a setting.

This was a rational response to what was an extraordinary change in the lives of these people.

I think that this reflected an intelligent assessment of what constituted the best course of action: collaboration and cooperation not passive acquiescence nor, apart from preliminary skirmishes, the use of force.

Perhaps the most compelling evidence for the rapid emergence of tacit consent to colonial rule was that a relatively very small number of colonial officials, distributed very thinly across the territory, could exert effective control over several million people.

My conclusion is that a combination of enlightened colonial policy and the rapid emergence of tacit consent to colonial rule, explains why Pax Australiana was able to be imposed in a largely peaceful way.

The peoples of PNG, by acting as they did, helped ensure that the worst excesses of European colonialism were not visited upon them.

In so doing, they also helped ensure a peaceful transition to eventual independence in a way that would have greatly pleased Sir William McGregor and Sir Hubert Murray, as well as those traditional Papua New Guinean leaders of long ago who rationally concluded that they faced a mostly benign colonial rule where the benefits outweighed the costs.

One day, a Papua New Guinea historian may subject the thesis outlined here to serious examination.

It is my hope and belief that it will hold up to even the closest interrogation.