Victor Davis Hanson writes; "... the Thuclydidean discourse on the plague [in Athens] becomes a reminder of how close humans always are to savagery - and how precious is their salvation won through law, religion, science and custom." (more)

The A on that map is Thermopylae where the famous last stand of the Spartans and Plateans occurred. The sea has moved back from the cliffs and is now far out into the plains due to 1600 years of erosion and weathering. Thermopylae is seen as the battle that saved the West from Persia and cemented the Spartans as the great warrior society of ancient times. But is it?

Thermopylae is certainly dramatic. The Spartans knew they would be out-numbered and in their highly militaristic state controlled society where a warrior's death in battle was romanticized as the highest form of civic good has resonated in narrative history and story telling since. But with a rational eye was it a pivotal battle. The answer has to be no.

The Spartans were bizarrely superstitious even for their semi-animistic times. As a consequence it was the Athenians and other city-states that often bore the brunt of the Persian intrusions into Greece. Other than the battle of Platea where the Spartans bore the brunt of Persian forces, the other battles were victories by the democratic city-state of Athens.

Prior to Thermopylae the Persians had brought an army over to Macedonia and Greece. The Athenians met them in set battle at Marathon. The Persians were routed. At the time Athens had just thrown off the irons of Tyranny and Aristocracy and was a newly minted form of self-government in democracy. Common today, but not then. The other Greek states watched to see if this new form of political and social organization would be able to withstand the pressures of war. It could. As Marathon showed.

The real reason that the Athenians won at Marathon was that their military weapons and the social organization of the Phalanx was superior to the Persian arms, armaments and battle formations. The armor of the Phalanx was bronze and the main weapon was the shield and spear. Coupled with the tightly disciplined formation of the Phalanx the wicker armor and charges of the Persians were no match.

Thermopylae and Platea showed again that despite the superior cavalry forces of the Persians, which were well used, once it came to set battle the Phalanx formation of the Spartans and Athenians was superior to the armor, weaponry and formations of the Persians.

When Xerces tried to force his way through to Attica and the Peloponnese he successfully got past the bottle neck of Thermopylae despite the valiant stand by the Spartans and Plateans. The Persian invading force - while large in numbers of land forces - was also an amphibious force of triremes. Like today, naval power in the Mediterranean allowed for power projection over a wide area. It was Athens naval empire that allowed it to survive the 30 year war with Sparta for such a long time after the Greeks had defeated the Persians.

The battle of Salamis was largely an expression of Athenian naval power. They soundly defeated the Persian fleet, even embarrassing the Phoenicians who were the Persian naval elite. Apparently Xerces was watching from a nearby hill as the battle unfolded. It was after this naval battle that he gave up personally seeing the Greeks brought to their knees and headed back to the Persian empire to bring the rebelling Babylonians back into line.

So like Marathon which ended the first invasion force, it was Salamis which blunted the Persian advance into Greece. The remaining Persian land forces were later defeated at Platea but it was the Athenians again who stopped the Persians.

Thermopylae is dramatic and has romance written all over it for the selflessness death of the Spartans, but in terms of being pivotal it was not. Marathon and Salamis largely established what was to be the Athenian empire through Greece and Ionia. It was also the rise of Athens that would lead them to ongoing conflict with Sparta during the Pelopponesian War as the two Greek powers fought what was a civil war for control of Greece.
Central to liberalism is that politics - the bartering of power in a public and social situation - is conducted through the mechanisms of debate, deliberation, consensus and the reaching of a point of least dissatisfaction between parties, faction and special interest groups such as minorities. Liberalism replaces violence through this process. Lintott compares the meeting of violence, cohesion and legislation in Athens to Rome:

Cohen [writing on Athens] argues that social cohesion was (and is) far more a product of the regulation and modification of conflicts between individuals and families through shared assumptions and understandings than the effects of rules imposed from above: the law at Athens merely provided new channels in which feuds, rivalries, and tensions played themselves out.

This is an important corrective to the traditional positive approach to law which tends to be held by lawyers but is itself no more than a half-truth.

The cohesion of Athenian democratic society was maintained to a great extent by Athenian social attitudes and political ideology, whereas there was a major division in Roman society even in the politically stable period of the middle republic.

Athenian and Roman constitutional practice grew in response to political crisis. Athens became a democracy at the hands of crisis, and increasingly democratic forms of Roman governance were also in response to constitutional failure - a good example being the plebians quieted with the creation of the constitutional position of Tribune.

Westminster has a muddly constitutional practice as well which only changes after each new crisis and in some cases does not learn at all from it. Australia has had numerous crisis with our form of Westminster including two over-throws of democratically elected executives, in the 30s and 70s, yet little in modification to solve those issues.

Canada is now having their own version of the same crisis where a weak Governor-General has allowed governance to hibernate - or prorogue - while the current minority government tries to shore up its control of the legislative. Something that will most likely end up in failure.

Westminster at the national, NSW and Qld level has most likely survived as the crisis was amongst political elites, and the majority was only affected as much as having to go to the ballot boxes to determine which elites get to win for the next three years.
Triremes were the dreadnoughts of the classical era. They were expensive and required a great deal of maritime expertise, not to mention social class cohesion, in order to be effective in battle. The Athenian democratic political structure led to Athens dominating the seas until losses in the latter part of the Peloponessian War meant a degradation of the quantitative and qualitative advantages they held over the Spartans.

Trireme from didactylos47's photostream

Equally important was the logistical structure supporting the triremes. This is true for most military endeavours; American hegemony currently is based upon American dominance of logistics such that their forces can maintain a high tempo indefinitely. This was also true of the British military in their hay day. Triremes were short range weapons heavily reliant on human labor at the oars. Consequently they needed constant water and food provisioning. (more)
During the Athenian Sicilian campaign the cavalry of the Syracuse became the dominant weapon on the battlefield, stifling the forty thousand strong Athenian hoplites from gaining the advantage in the field. The Athenians in return raised their own cavalry and sent it to Sicily. They weren't the knights of medieval times though, they were small ponies, approximately four and half feet tall, and they lacked stirrups. Hardly frightening, except the Greeks of that time were tiny. Hanson writes:

These tiny mounts, mostly stallions, were only partialled protected with light cloth padding over the face, thighs and chest, and harder to ride than geldings.

It was hard to train riders to control the stallions as well as handle a spear and blade in battle. (more)
Cunning Realist writes on trauma cocktails which effectively make a nation accept anything; breaking down individual and social norms such that extremes become accepted as the new norm.

One of the interesting aspects of the Peloponnesian War was that the normal method of determining conflict between Greek city-states, hoplite battle, was replaced with political and ethnic genocide. Asymmetric warfare ruined the wealth, morality and power of Greece such that the Macedonians and then the Romans replaced them as the centre of Mediterranean power. (more)
America is the current global hegemon, so it is always possible to make analogies with the US and prior super-powers such as Britain, Rome, and even Athens. Victor Davis Hanson looks at the analogies between America and Athens in A War Like No Other. One of the curiosities of Sparta was that they would promise to bring tyranny to the states they liberated from Athenian democracy. Tyranny back then being a legitimate government form while democracy was the radical, liberal and egalitarian form of subversiveness. (more)
Cam Riley: South Sea Republic. Freedom, liberty, equity and an Australian Republic.