Of course, this scholarship continues to ignore the clear evidence of a huge copper trade between the Americas and the Old world. Bronze manufacturing required strong local sponsorship in the form of the palace economies described herein. These factories were the sub factories of a global copper trade that passed through the Atlanteans.
I suspect that the Atlantean fleet of perhaps a real ten thousand ships like they love to claim in Homer was making itself felt along the Egyptian coast in the years prior to the Hekla blast. They had unity and a system of confederate palace states. Recall that these were not particularly large cities so much a palace household and retainers. The surrounding population surely benefited and was certainly ruled by this caste of merchant princes who traded value for value. That all ended abruptly with the loss of the copper trade. These palaces were all then overthrown.
More critically, the surviving populations in Europe faced a twenty year collapse of their livelihoods and those that could took ship and joined in a sea borne migration into the Eastern Mediterranean. This was likely expressed as colonization including Gaza, Athens and Carthage, where already established factories were in position to absorb the refugees. We may never develop the details, but the advent of a surplus of desperate pirates surely explains the swift collapse of the many isolated trade palaces.
The other putative possibilities of causation are simply insufficient and were all easily handled in the course of business as usual. An influx of the desperate from the north was another matter and these guys were the original pro0viders of the best weapons. Is it any surprise that they were able to make the Egyptian state accommodate them? And recall that this was the single largest and strongest state in front of them.
Imagine a group of refugees landing in New Jersey and forcing the USA to make room for them? Pretty good trick even at a three thousand year remove.
This entry also confirms that iron was not seriously used until the loss of the copper trade. This clearly implies that the copper trade and its control was the road to wealth. Bronze made excellent weapons that were not likely surpassed by iron for centuries. They were simple to cast and work harden in the forge whereas iron needed to be laboriously converted into steel in very small batches.
In fact steel making did not change at all right into the industrial age which is why cannons were first made from bronze, then cast iron and then, very late in the day from steel. What this means is that had copper been available, the use of bronze would certainly have continued centuries more.
Bronze Age collapse --- From Wikipedia, the free encyclopedia
The Bronze Age collapse is the name given by those historians who see the transition from the Late Bronze Age to the Early Iron Age, as violent, sudden and culturally disruptive, expressed by the collapse of palace economies of the Aegean and Anatolia, which were replaced after a hiatus by the isolated village cultures of the Dark Ages period of history of the Ancient Near East. The Bronze Age collapse may be seen in the context of a technological history that saw the slow, comparatively continuous spread of iron-working technology in the region, beginning with precocious iron-working in what is now Romania in the 13th and 12th centuries. The cultural collapse of the Mycenaean kingdoms, the Hittite Empire in Anatolia and Syria, and the Egyptian Empire in Syria and Canaan, bringing the scission of long-distance trade contacts and sudden eclipse of literacy, occurred between 1206 and 1150 BCE. In the first phase of this period, almost every city between Troy and Gaza was violently destroyed, and often left unoccupied thereafter (for example, Hattusas, Mycenae, Ugarit).
The gradual end of the Dark Age that ensued saw the rise of settled Neo-Hittite Aramaean kingdoms of the mid-10th century BCE, and the rise of the Neo-Assyrian Empire.
Main article: Downfall of the Hittite Empire
Every site important during the preceding Late Bronze Age shows a destruction layer, and it appears that here civilization did not recover to the same level as that of the Hittites for another thousand years. Hattusas, the Hittite capital, was burned and abandoned, and never reoccupied. Karaoglan was burned and the corpses left unburied. Troy was destroyed at least twice, before being abandoned until Roman times.
The catastrophe separates Late Cypriot II (LCII) from the LCIII period, with the sacking and burning of the sites of Enkomi, Kition, and Sinda, may have occurred twice, before being abandoned. A number of sites, though not destroyed, were also abandoned. Kokkinokremos was a short-lived settlement, where the presence of various caches concealed by smiths suggests that none ever returned to reclaim the treasures, suggesting they were killed or enslaved.
Syrian sites previously showed evidence of trade links with Egypt and the Aegean in the Late Bronze Age. Evidence at Ugarit shows that the destruction there occurred after the reign of Merenptah, and even the fall of Chancellor Bay. Letters on clay tablets found baked in the conflagration of the destruction of the city speak of attack from the sea, and a letter from Alashiya (Cyprus) speaks of cities already being destroyed from attackers who came by sea. It also speaks of the Ugarit fleet being absent, patrolling the coast.
None of the Mycenaean palaces of the Late Bronze Age survived, with destruction being heaviest at palaces and fortified sites. Up to 90% of small sites in the Peloponnese were abandoned, suggesting a major depopulation. The End Bronze Age collapse marked the start of what has been called the Greek Dark Ages, which lasted for more than 400 years. Other cities, like Athens, continued to be occupied, but with a more local sphere of influence, limited evidence of trade and an impoverished culture, from which it took centuries to recover.
Main article: Third Intermediate Period of Egypt
After apparently surviving for a while, the Egyptian Empire collapsed in the mid twelfth century BCE (during the reign of Ramesses VI). Previously the Merneptah Stele spoke of attacks from Lybians, with associated people of Ekwesh, Shekelesh, Lukka, Shardana and Tursha or Teresh, and a Canaanite revolt, in the cities of Ashkelon, Yenoam and the people of Israel. A second attack during the reign of Ramesses III involved Peleset, Tjeker, Shardana and Denyen.
Robert Drews describes the collapse as "the worst disaster in ancient history, even more calamitous than the collapse of the Western Roman Empire". A number of people have spoken of the cultural memories of the disaster as stories of a "lost golden age". Hesiod for example spoke of Ages of Gold, Silver and Bronze, separated from the modern harsh cruel world of the Age of Iron by the Age of Heroes.
As part of the Late Bronze Age-Early Iron Age Dark Ages, it was a period associated with the collapse of central authorities, a general depopulation, particularly of highly urban areas, the loss of literacy in Anatolia and the Aegean, and its restriction elsewhere, the disappearance of established patterns of long-distance international trade, increasingly vicious intra-elite struggles for power, and reduced options for the elite if not for the general mass of population.
There are various theories put forward to explain the situation of collapse, many of them compatible with each other.
Amos Nur shows how earthquakes tend to occur in "sequences" or "storms" where a major earthquake above 6.5 on the Richter magnitude scale can in later months or years set off second or subsequent earthquakes along the weakened fault line. He shows that when a map of earthquake occurrence is superimposed on a map of the sites destroyed in the Late Bronze Age, there is a very close correspondence. 
Ekrem Akurgal, Gustav Lehmann and Fritz Schachermeyer, following the views of Gaston Maspero have argued on the basis of the wide spread findings of Naue II-type swords coming from South Eastern Europe, and Egyptian records of "northerners from all the lands"
The Ugarit correspondence draws attention to such groups as the mysterious Sea Peoples. Equally, translation of the preserved Linear B documents in the Aegean, just before the collapse, demonstrates a rise in piracy and slave raiding, particularly coming from Anatolia. Egyptian fortresses along the Libyan coast, constructed and maintained after the reign of Ramesses II were constructed to reduce raiding.
Leonard R. Palmer suggested that iron, whilst inferior to bronze weapons, was in more plentiful supply and so allowed larger armies of iron users to overwhelm the smaller armies of bronze-using maryannu chariotry. This argument has been weakened of late with the finding that the shift to iron occurred after the collapse, not before. It now seems that the disruption of long distance trade, an aspect of "systems collapse", cut easy supplies of tin, making bronze impossible to make. Older implements were recycled and then iron substitutes were used.
On the other hand, technology cannot be so quickly dismissed as a factor. The invention of the technology of metallurgy is not generally regarded as a Paradigm Shift, in a class with the technologies of agriculture, city-building, industry and electronics. Yet metalworking had a profound impact on the course of mankind's development. Warfare on the scale with which we are familiar today was not possible when sharpened sticks and flint points and blades were the only weapons available. The first bronze swords and armor were surely regarded as "weapons of mass destruction" by the last inhabitants of stone age cities because of the carnage they made possible.
Still, the very nature of bronze, an alloy of copper and tin, forces at least a grudging equilbrium on man's violent nature. Deposits of copper ore and tin ore almost never occur in the same region. In order to make bronze, two cities a fair distance apart must maintain peaceful relations and trade raw materials with each other.
Iron metallurgy destroyed this equilibrium. Only one ore is required to make iron artifacts, and deposits of it are abundant. The only trick to smelting iron is the creation of hitherto unimaginably high temperatures, because the melting point of iron is hundreds of degrees higher than that of copper and tin. But once that information became well known, there was nothing to stop even the most uncivilized of the remaining Neolithic tribes from arming their warriors, proclaiming themselves "kingdoms," and attacking the cities. Even worse, the cities were no longer dependent on each other for complementary ores, and had no more reason to maintain peaceful relations.
The Iron Age may not have been the cause of the collapse of civilization in its first place of origin, but it is difficult to dismiss iron as a possible reason for its slow recovery.
Barry Weiss , using the Palmer Drought Index for 35 Greek, Turkish, and Middle Eastern weather stations, showed that a drought of the kinds that persisted from January 1972 would have affected all of the sites associated with the Late Bronze Age collapse. Drought could have easily precipitated or hastened socio-economic problems and led to wars. More recently Brian Fagan, has shown how the diversion of mid-winter storms from the Atlantic were diverted to travel north of the Pyrenees and the Alps, bringing wetter conditions to Central Europe, but drought to the Eastern Mediterranean, was associated with the Late Bronze Age collapse
Main article: Societal collapse
A general systems collapse has been put forward as an explanation for the reversals in culture that occurred between the Urnfield culture of the 12-13th centuries BCE and the rise of the Celtic Hallstatt culture in the 9th and 10th centuries. This theory may, however, simply beg the question as to whether this collapse was the cause of or the effect of the Bronze Age collapse being discussed. General Systems Collapse theories have been pioneered by Joseph Tainter who shows how social declines in return to complexity leads often to collapse to simpler forms of society.
In the specific context of the Middle East a variety of factors - including population rise, soil degradation, drought, cast bronze weapon and iron production technologies - conceivably could have combined to push the relative price of weaponry compared to arable land to a level that ultimately proved to be beyond the control of traditional warrior aristocracies.
Robert Drews argues that the appearance of massed infantry, using newly developed weapons and armor, such as cast rather than forged spearheads and long swords, a revolutionizing cut-and-thrust weapon, and javelins, the appearance of bronze foundries itself suggesting "that mass production of bronze artifacts was suddenly important in the Aegean". Homer uses "spears" as a virtual synonym for "warrior" suggesting the continued importance of the spear in combat. Such new weaponry, furnished to a proto-hoplite model who were able to withstand attacks of massed chariotry, destabilized states that were based upon the use of chariots by the ruling class and precipitated an abrupt social collapse when raiders and/or infantry mercenaries were able to conquer, loot, and burn the cities.(-5-)
^ See A. Stoia and the other essays in M.L. Stig Sørensen and R. Thomas, eds., The Bronze Age—Iron Age Transition in Europe (Oxford) 1989, and T.H. Wertime and J.D. Muhly, The Coming of the Age of Iron (New Haven) 1980.
^ Drew 1993:1 quotes Fernand Braudel's assessment that the Eastern Mediterranean cultures returned almost to a starting-point ("plan zéro"), "L'Aube", in Braudel, F. (Ed) (1977), La Mediterranee: l'espace et l'histoire (Paris)
^ Nur, Amos and Cline, Eric; (2000) "Poseidon's Horses: Plate Tectonics and Earthquake Storms in the Late Bronze Age Aegean and Eastern Mediterranean", Journ. of Archael. Sc. No 27 pps.43-63 - http://srb.stanford.edu/nur/EndBronzeage.pdf
^ Robbins, Manuel (2001) Collapse of the Bronze Age: the story of Greece, Troy, Israel, Egypt and Peoples of the Sea" (Authors Choice Press)
^ Palmer, Leonard R (1962) Mycenaeans and Minoans: Aegean Prehistory in the Light of the Linear B Tablets. (New York, Alfred A. Knopf, 1962)
^ Weiss, Barry: (1982) "The decline of Late Bronze Age civilization as a possible response to climatic change" in Climatic Change ISSN 0165-0009 (Paper) 1573-1480 (Online), Volume 4, Number 2, June 1982, pps 173 - 198
^ Fagan, Brian M. (2003), "The Long Summer: How Climate Changed Civilization (Basic Books)
^ http://www.iol.ie/~edmo/linktoprehistory.html - a page about the history of Castlemagner, on the web page of the local historical society
^ Tainter, Joseph (1976)"The Collapse of Complex Societies" (Cambridge University Press)
^ Drews pp192ff.
^ The Naue Type II sword, introduced from the eastern Alps and Carpathians ca 1200, quickly established itself and became the only sword in use during the eleventh century; iron was substituted for bronze without essential redesign (Drews 1993:194.
^ Drews, R. (1993) The End of the Bronze Age: Changes in Warfare and the Catastrophe ca. 1200 B.C. (Princeton 1993).
Oliver Dickinson, The Aegean from Bronze Age to Iron Age: Continuity and Change Between the Twelfth and Eighth Centuries BC Routledge (2007), ISBN 978-0415135900.