It seems to me an utter impossibility that the 'true' colonies could have developed without slavery. It also interestingly points to the tension between small farmers and capitalists which I tend to speculate is the basis of a lot of ideas in the U.S. of freemen. The idea that one can build for ones self a life off the land taken from the natives such that they no longer need to work for someone else but have their own property. This lead to the decentralized government because such people were not to be readily subdued by government and for a long time, many places were pretty 'wild' and relied not on government policy but communal norms to govern life and would run out any big wig that came through.
This chiefly arose in my mind in the writings of E. G. Wakefield when considering colonial economies of colonies where there wasn't a significant infrastructure to exploit due to small scale tribal life such as in the US and Australia.
Labor simply wasn't able to be coerced due to the access of stolen native land.
I did not, you know, intend to become a farmer. Having fortune enough for all my wants, I proposed to get a large domain, to build a good house, to keep enough land in my own hands for pleasure-grounds, park, and game preserves; and to let the rest, after erecting farm-houses in the most suitable spots. My mansion, park, preserves, and tenants, were all a mere dream. I have not one of them. When, upon my first arrival, I talked of these things to some sensible men, to whom I was recommended, they laughed in my face. I soon found that a house would, though the stone and timber were to be had for nothing, cost three times as much as in England. This was on account of the very high wages required by mechanics; but this was not all. None of the materials of a house, except stone and timber, are produced in the colony. Every pane of glass, every nail, every grain of paint, and every piece of furniture, from the kitchen copper to the drawing-room curtains, must have come from England. My property is at a distance of nearly seventy miles from the sea, and there is no road, but a track through the forest, for two-thirds of that distance. Every thing, even the food of the labourers, must have been transported from afar. Log-houses must have been built for the labourers; and the cheapest way of providing for them would have been by the establishment of a farm, in the first instance, to produce enough for their subsistence. Lastly, though none of these obstacles had existed, the whole colony did not contain as many masons, carpenters, glaziers, painters, black and whitesmiths, and other mechanics, as I should have required. You may believe most statements of fact respecting the colony; but beware how you draw conclusions!
Of course, I soon abandoned all thought of building a mansion. As for a park, my whole property was a park, and a preserve for kangaroos and emus. The grand object was to dispark it as soon as possible. I clung for some time to the hope of having tenants; but you will readily see that what deterred me from building a mansion presented numerous obstacles to the erection of farm-houses. Besides, even though I had forced circumstances, and had, at an enormous cost, placed a dozen good homesteads on my land, where was I to find tenants? There is no such class as a tenantry in this country, where every man, who has capital to cultivate a farm, can obtain one of his own for nothing. I soon found that what little my twenty thousand acres had cost me would be entirely lost, unless I turned farmer myself, and endeavoured, by my own exertions, with the assistance of convict servants, to extract something from the soil.
I constantly ask myself, whether it be possible to devise any means by which to establish, in a new country, such a proportion between people and land as would render labour plentiful, and not extravagantly dear. Here we have, it is true, a species of slave-labour that of convicts, and our system of slavery has been peculiarly favourable to the master, because the slaves have been obtained without any prime cost. To this, combined with the demand for produce created by the great expenditure of Government, the few rich men of New South Wales are wholly indebted for their fortunes. But the supply of cheap labour was always small and variable; and, of late, the demand has so much increased, through the increase of landowners, that not the slightest dependence can be placed on convict labour as a permanent source of wealth. You may obtain, though not without trouble, one, two, or perhaps three, convicts, for a term of a few years; but that they will rob you, is almost certain; that they will murder you, is by no means improbable; and that their labour will not be very profitable, is beyond a doubt. What, then, are we to do, to obtain that desirable proportion between the demand and supply of labour, without which, I say, no country can flourish? Answer me that question satisfactorily, and I will tell you that Botany Bay is an earthly paradise. This, indeed, would be a glorious discovery. Call it an invention, or what you will, it must, whenever established in a country cursed with slavery, cause the natural, slow, easy death of that hideous monster. Fancy the slavery of America and South Africa in a slow consumption, and free labour growing up, healthy, strong, and cheerful, to supply its place! But I am dreaming—We have a right to presume that slavery will flourish in America and South Africa, until there shall be no more land to be obtained for next to nothing; and that the inhabitants of Australasia must, for hundreds of years to come, secretly long for a trade in human flesh. Tell me the time when the disproportion between the demand and supply of labour in America, South Africa, and Australasia will cease, and I will tell you when slavery will cease in America and South Africa, and when the Australasians will become a rich, instructed, refined, and highly civilized people. Meanwhile, I deliberately state it as my opinion, that a permission to obtain slaves from Africa would be most beneficial to these settlements, with a view only to wealth and civilization; and that if Australasia should become independent to-morrow, these people would find some means of establishing slavery in spite of all the saints.
But will transportation continue to exert the same happy influence on our condition? t think not. If, for every acre of land that may be appropriated here, there should be a conviction for felony in England, our prosperity would rest on a solid basis; but, however earnestly we may desire it, we cannot expect that the increase of crime will keep pace with the spread of colonization. What, then, must happen? Every day sees an increase in the number of employers of labour, without a proportionate increase in the number of labourers. As convicts are fairly distributed amongst those who want them, the general increase of demand diminishes the supply to each settler. Twenty thousand convicts, divided amongst five hundred settlers, would give to each settler forty pair of bands, wherewith to obtain for his wife a superb landau and plenty of gunpowder; but divide the same number of convicts amongst ten times the number of settlers, and poverty, in respect to every thing above mere subsistence, must be the lot of all. During forty years we have combined the fire and water of political economy—cheap land and cheap labour. The result is, no doubt, astonishing: but, as that strange union of contradictions is almost at an end, so what it has produced will vanish like a steam-cloud produced by the fire and water of physics, which can be maintained only by the constant action of its cause. The union of cheapness of labour with cheapness of land depended on the proportion which labour bore to appropriated land. Alter that proportion, either by diminishing the quantity of labour, or increasing the quantity of land, and you dissolve the unnatural union. Every day, I must repeat, sees an increase in the quantity of; land, whilst the quantity of labour remains the same. Ten years hence land will be as cheap as ever, and we shall talk of cheap labour as a thing that was. Ten years hence, perhaps sooner, the peculiar cheapness of land, which is a natural attribute of this country, must operate without a check; the accumulation of wealth must cease; and most of that creation from nothing, which astonishes the hasty observer, will gradually perish.
The effect of penal slavery in producing wealth must, as has been already explained, depend altogether on the proportion of cheap slaves to the employers of slave-labour. If, henceforth, convicts shall be fairly divided amongst all who want labourers, they will not confer wealth upon any man. If they should be unfairly distributed by favour, so as to bestow upon a few persons only the means of wealth, that would not be a general benefit; and such partiality would be injurious, in another light, by causing furious ill-will amongst the colonists.
Marx applauds E.G. Wakefield for his honesty in considering the issue so forthrightly.
He lays bare something which may be hidden in the economics of others who naturalize such relations as true of production in general, missing the rather specific social relations which are a precondition for capital to be possible. In fact, the opposition of people who produce their own subsistence is clearly at odds with capitalist production which requires them to be propertyless and without means to survive other than to work for money to exchange for their needs. Such a coercive deprivation is absolutely necessary otherwise one would clearly come up against the point that no one would want to work for you because what need would they necessary have of money unless as a supplement to their primary means of life?
Political economy confuses on principle two very different kinds of private property, of which one rests on the producers’ own labour, the other on the employment of the labour of others. It forgets that the latter not only is the direct antithesis of the former, but absolutely grows on its tomb only. In Western Europe, the home of Political Economy, the process of primitive accumulation is more of less accomplished. Here the capitalist regime has either directly conquered the whole domain of national production, or, where economic conditions are less developed, it, at least, indirectly controls those strata of society which, though belonging to the antiquated mode of production, continue to exist side by side with it in gradual decay. To this ready-made world of capital, the political economist applies the notions of law and of property inherited from a pre-capitalistic world with all the more anxious zeal and all the greater unction, the more loudly the facts cry out in the face of his ideology. It is otherwise in the colonies. There the capitalist regime everywhere comes into collision with the resistance of the producer, who, as owner of his own conditions of labour, employs that labour to enrich himself, instead of the capitalist. The contradiction of these two diametrically opposed economic systems, manifests itself here practically in a struggle between them. Where the capitalist has at his back the power of the mother-country, he tries to clear out of his way by force the modes of production and appropriation based on the independent labour of the producer. The same interest, which compels the sycophant of capital, the political economist, in the mother-country, to proclaim the theoretical identity of the capitalist mode of production with its contrary, that same interest compels him in the colonies to make a clean breast of it, and to proclaim aloud the antagonism of the two modes of production. To this end, he proves how the development of the social productive power of labour, co-operation, division of labour, use of machinery on a large scale, &c., are impossible without the expropriation of the labourers, and the corresponding transformation of their means of production into capital. In the interest of the so-called national wealth, he seeks for artificial means to ensure the poverty of the people. Here his apologetic armor crumbles off, bit by bit, like rotten touchwood. It is the great merit of E.G. Wakefield to have discovered, not anything new about the Colonies , but to have discovered in the Colonies the truth as to the conditions of capitalist production in the mother country. As the system of protection at its origin  attempted to manufacture capitalists artificially in the mother-country, so Wakefield’s colonisation theory, which England tried for a time to enforce by Acts of Parliament, attempted to effect the manufacture of wage-workers in the Colonies. This he calls “systematic colonisation.”
First of all, Wakefield discovered that in the Colonies, property in money, means of subsistence, machines, and other means of production, does not as yet stamp a man as a capitalist if there be wanting the correlative — the wage-worker, the other man who is compelled to sell himself of his own free will. He discovered that capital is not a thing, but a social relation between persons, established by the instrumentality of things.  Mr. Peel, he moans, took with him from England to Swan River, West Australia, means of subsistence and of production to the amount of £50,000. Mr. Peel had the foresight to bring with him, besides, 300 persons of the working class, men, women, and children. Once arrived at his destination, “Mr. Peel was left without a servant to make his bed or fetch him water from the river.”  Unhappy Mr. Peel who provided for everything except the export of English modes of production to Swan River!
For the understanding of the following discoveries of Wakefield, two preliminary remarks: We know that the means of production and subsistence, while they remain the property of the immediate producer, are not capital. They become capital only under circumstances in which they serve at the same time as means of exploitation and subjection of the labourer. But this capitalist soul of theirs is so intimately wedded, in the head of the political economist, to their material substance, that he christens them capital under all circumstances, even when they are its exact opposite. Thus is it with Wakefield. Further: the splitting up of the means of production into the individual property of many independent labourers, working on their own account, he calls equal division of capital. It is with the political economist as with the feudal jurist. The latter stuck on to pure monetary relations the labels supplied by feudal law.
“If,” says Wakefield, “all members of the society are supposed to possess equal portions of capital... no man would have a motive for accumulating more capital than he could use with his own hands. This is to some extent the case in new American settlements, where a passion for owning land prevents the existence of a class of labourers for hire.”  So long, therefore, as the labourer can accumulate for himself — and this he can do so long as he remains possessor of his means of production — capitalist accumulation and the capitalistic mode of production are impossible. The class of wage labourers, essential to these, is wanting. How, then, in old Europe, was the expropriation of the labourer from his conditions of labour, i.e., the co-existence of capital and wage labour, brought about? By a social contract of a quite original kind. “Mankind have adopted a... simple contrivance for promoting the accumulation of capital,” which, of course, since the time of Adam, floated in their imagination, floated in their imagination as the sole and final end of their existence: “they have divided themselves into owners of capital and owners of labour.... The division was the result of concert and combination.”  In one word: the mass of mankind expropriated itself in honor of the “accumulation of capital.” Now, one would think that this instinct of self-denying fanaticism would give itself full fling especially in the Colonies, where alone exist the men and conditions that could turn a social contract from a dream to a reality. But why, then, should “systematic colonisation” be called in to replace its opposite, spontaneous, unregulated colonisation? But - but - “In the Northern States of the American Union; it may be doubted whether so many as a tenth of the people would fall under the description of hired labourers.... In England... the labouring class compose the bulk of the people.”  Nay, the impulse to self-expropriation on the part of labouring humanity for the glory of capital, exists so little that slavery, according to Wakefield himself, is the sole natural basis of Colonial wealth. His systematic colonisation is a mere pis aller, since he unfortunately has to do with free men, not with slaves. “The first Spanish settlers in Saint Domingo did not obtain labourers from Spain. But, without labourers, their capital must have perished, or at least, must soon have been diminished to that small amount which each individual could employ with his own hands. This has actually occurred in the last Colony founded by England — the Swan River Settlement — where a great mass of capital, of seeds, implements, and cattle, has perished for want of labourers to use it, and where no settler has preserved much more capital than he can employ with his own hands.” 
We have seen that the expropriation of the mass of the people from the soil forms the basis of the capitalist mode of production. The essence of a free colony, on the contrary, consists in this — that the bulk of the soil is still public property, and every settler on it therefore can turn part of it into his private property and individual means of production, without hindering the later settlers in the same operation. This is the secret both of the prosperity of the colonies and of their inveterate vice — opposition to the establishment of capital. “Where land is very cheap and all men are free, where every one who so pleases can easily obtain a piece of land for himself, not only is labour very dear, as respects the labourer’s share of the produce, but the difficulty is to obtain combined labour at any price.” 
-For Ethical Politics