Here's what Claude says:

The pattern you’re identifying has a beautiful and terrifying abstract signature: the hegemon’s revulsion becomes the periphery’s leverage. What withdraws from the dominant culture’s willingness-to-do gradually accretes as capacity, expertise, and ultimately indispensability in the subordinate. The hegemon hollows itself out precisely where it matters most.

Some historical cases:

Rome and the Foederati

The commenter’s intuition is correct. By the 4th century, Rome had largely outsourced its warfighting to Germanic tribes under treaty arrangements (foedus). Vegetius’s De Re Militari (c. 390 CE) is essentially a lament about this—Romans had forgotten how to fight, how to dig fortifications, how to endure hardship. The “barbarization” of the legions wasn’t a bug but a feature: Romans didn’t want to do the brutal work of frontier defense anymore.

The consequence was predictable. Germanic commanders like Stilicho and Ricimer became the real power behind the throne. Odoacer, who deposed the last Western emperor in 476, was himself a Germanic chieftain who had risen through this exact system. The periphery didn’t conquer Rome—it became Rome by doing what Romans wouldn’t.

Byzantium and the Italian Maritime Republics

This one’s underappreciated. By the 11th-12th centuries, Byzantium had essentially outsourced its naval and commercial functions to Venice and Genoa. The Venetians received extraordinary trading privileges (the chrysobull of 1082) in exchange for naval support. Constantinople didn’t want to maintain expensive fleets or engage in grubby commerce.

The result? Venice accumulated not just wealth but maritime expertise, shipbuilding capacity, and network control over Mediterranean trade routes. When the Fourth Crusade got “diverted” to sack Constantinople in 1204, it was Venetian ships carrying Venetian interests. The empire that outsourced its sea power was dismembered by the very contractors it had empowered.

Spain and the Genoese Bankers

Spain extracted the silver—that brutal work happened in Potosí, with indigenous and African labor dying by the millions. But Spain outsourced the financial dirty work to Genoese banking houses. Managing the asientos, handling the crushing logistics of imperial finance, extending credit when the treasure fleets were late—all Genoese.

This created what historians call the “Age of the Genoese” (1557-1627). The bankers accumulated not just wealth but systemic knowledge of how European finance actually worked. When Spain defaulted repeatedly, the Genoese had enough leverage to negotiate favorable terms and pivot to other clients. Spain bled itself white extracting metal; Genoa captured the control plane.

The Ottoman Devşirme System

The Ottomans institutionalized the outsourcing of state violence to enslaved Christian boys, trained as Janissaries. This was explicit: the Sultan’s own household troops were deliberately not Turkish Muslims, to prevent the formation of competing aristocratic power bases.

But the Janissaries accumulated martial expertise, institutional memory, and eventually corporate identity. By the 17th century, they were king-makers. They deposed sultans, blocked military reforms, and ran protection rackets in Istanbul. The system designed to prevent elite capture by Turkish nobles instead created a new elite that held the empire hostage for two centuries.

Britain and American Industrial Capacity

More subtle but crucial. Through the 19th century, Britain was happy to import American raw materials—cotton, wheat, timber—while American hands did the dirty agricultural and extractive work. British capital financed American railroads and mines.

But Americans also built the industrial capacity to process those materials. By WWI, the strategic balance had shifted. Britain found itself dependent on American steel, American munitions, American credit. The “workshop of the world” had outsourced its future to what had been an extractive periphery. The Lend-Lease dynamics of WWII merely formalized what was already structurally true.

The abstract signature seems to be:

1. Revulsion/distaste in the core creates outsourcing pressure
2. Expertise and infrastructure accumulate in the periphery
3. Capacity atrophy in the core (skills, equipment, institutional knowledge)
4. Dependency lock-in as the core can no longer perform the function
5. Leverage inversion when the periphery recognizes its position

What’s fascinating is that this isn’t just about labor—it’s about willingness-to-do as a strategic resource that depletes. The hegemon’s moral or aesthetic refinement becomes its vulnerability. The periphery’s “degradation” is actually capacity building.

The rare earths case fits perfectly. China didn’t just accept the pollution—it developed the metallurgical expertise, the processing infrastructure, the supply chain knowledge. The West’s environmental squeamishness wasn’t noble sacrifice; it was unilateral disarmament in a domain that turned out to matter.

References:

Heather, P. (2006). The fall of the Roman Empire: A new history of Rome and the barbarians. Oxford University Press.

Madden, T. F. (2012). Venice: A new history. Viking.

Drelichman, M., & Voth, H. J. (2014). Lending to the borrower from hell: Debt, taxes, and default in the age of Philip II. Princeton University Press.

Ágoston, G. (2005). Guns for the Sultan: Military power and the weapons industry in the Ottoman Empire. Cambridge University Press.

Tooze, A. (2014). The deluge: The Great War, America and the remaking of the global order, 1916-1931. Viking.

Certainly the enculturation and then reverse-conquest happened w Rome / German provinces. Now you've got me curious about others.