The Collapse of the Roman Republic...

As a sometime historian, I have read a full gamut on how and why the Roman Republic collapsed.  Often times, accademics tend to long winded and rambling explainations why the Republic collapsed and the

Empire was formed.  Over at The Volokh Conspiracy, there's a lively discussion going on this subject. 

It originates with a paper written by Eric Posner, who formerly wrote for the TVC.  His argument is based upon,  

The constitution of the Roman Republic featured a system of checks and balances that would eventually influence the American founders, yet it had very different characteristics from the system of separation of powers that the founders created. The Roman senate gave advice but did not legislate; the people voted directly on bills and appointments in popular assemblies; and a group of magistrates, led by a pair of consuls, proposed bills, brought prosecutions, served as judges, led military forces, and performed other governmental functions. This paper analyzes the Roman constitution from the perspective of agency theory, and argues that the extensive checks and balances, which were intended to prevent the recurrence of monarchy, may have gone too far. Suitable for an earlier period in which the population was small and the political class was homogeneous, the constitution proved unworkable when Rome acquired a vast, diverse empire. The lessons of Roman constitutionalism for the American constitution are also discussed

The discussion in the comments is excellent, and to the point with very little snark.  The best point made in brief WHY the Roman Republic collapsed is by Drew Hoo who says,

1. The checks and balances in the Roman Constitution are overplayed. It’s true that, formally speaking, power was divided among these various groups, but Roman society was hierarchical and patronage-based in the extreme, and the people with the wealth and prestige ran things to a greater degree than one might think by just looking at the republic’s institutional structure.
2. The analysis I’ve seen in this thread does not give enough weight to the economic factors in the fall of the Republic. Traditionally, the backbone of the Roman army was formed by the small-landowner class. These men were unpaid and had to supply their own equipment, so warmaking was a rather bad business for them. The constant and far-ranging wars of the 3rd and 2nd centuries BC, combined with the depredations of Hannibal’s invasion of Italy, fatally weakened this part of society. At the same time, the nobiles gained huge amounts of wealth through the acquisition of land from overseas conquests and failed small farmers, staffing these plantations with the massive influx of war captives acquired through the Republic’s expansion. Because the traditional class which formed the bulk of the army was destroyed, the Republic was forced to turn the landless to populate its armies. These men, being beholden to their commanders for pay and for settlement upon their retirement, could be used by these leaders for their own purposes, with the consequences you well know.  [emphasis is mine, Ed.]
3. Can anybody who can see the full paper give us a sense of what sources the author used/historians he consulted? Without seeing the paper, my first thought was that it seems rather presumptuous for him to assume that he can get a professional’s grasp of the Roman Republic’s workings, enough so that he would think to publish a paper on it. DrewHoo(Quote)  November 5, 2010, 12:07 pm

There can be some parallels to what is occuring today in America.  The burden of taxation has begun to fall very heavily upon the middle class.  Furthermore, our "ruling elite" has becom less and less connected to our republic and has become more interested in amassing power for themselves.  Glenn Reynolds of Instapundit fame has this take,

I think the Roman Republic ended because its political class had more loyalty to themselves than to the republic.

This is connected to a comment on a prior post by a long time political operative I received last night.  I've eliminated all but historical names...

If you take a look at the record of XXXXXXXXX, you will quickly discover that he has always been part of the problem and never part of the solution. I don't mind partisan politics, as that seems to be the mainstay of our system, but I have met XXXXXXXX and I can honestly tell you that he is an elitist, arrogant, snob who will destroy the XXXXXXXX party before the next election. If you remember Huey Long from Louisiana, XXXXXX is cut from the same mold. He could care less about America, Americans, Jobs, Balanced Budgets, Immigration Reform, cutting back on federal spending. He is a vindictive hill billy from a backwater state. When we talked, I really thought I was talking to one of the dumbest members of the Senate...

That in  a nutshell is why our system is beginning to produce narcissistic politicians who for reasons of hubris, believe they are "the one" to solve all our problems...and only make them worse.