The ultimate results of the high-handed Athenian policy in the Delian League were first the destruction of the Athenian Empire, and in the long run, the destruction of the polis as the main form of government in Greece.
The destruction of the Athenian Empire was achieved by two serious wars between Athens and Sparta at the end of the 400s. These wars are known as the Peloponnesian Wars (431-421, 415-404). You may remember that the Spartans usually tried to prevent the growth of powerful states in Greece as part of their traditional foreign policy. Thus, they viewed the growth of Athenian power with alarm, and that eventually led to the outbreak of hostilities. Almost every state in the Greek world was involved in the war on one side or the other.
On the Athenian side, the wars did not go well because the assembly made all of the decisions. In a time of crisis, it is difficult to make consistent policies when everybody has to be consulted about them. If Pericles had lived, Athens might have won; but he died in 429, and the later Athenian leaders were not as capable as Pericles.
The greatest Spartan problem was that Athens controlled the sea. By the second war, it became evident that Sparta must have a navy to defeat the Athenians. In 412, Sparta made a deal with the Persians to return the Ionian cities to Persia in exchange for money to build ships. That is how the Spartans eventually won out.
The destruction of the political power of the polis was a much more gradual process. It is evident from 404 to 338 B.C. Like many great conflicts, the Peloponnesian Wars disillusioned most of the Greeks who participated in them. Greeks had once believed that loyalty to a polis was the most important feeling that a man could have. But they now saw that such loyalty could lead to terrible destruction. After 404, loyalty to the state is replaced by more personal concerns and interests. Moreover, the example which Athens had set was an invitation to other cities to create similar empires based on alliances in the Aegean.
Following the war, Sparta abandoned her conservative foreign policy and forced many other states into one-sided alliances with her. In the 370s, another polis, Thebes, tried the same thing. These efforts at imperialism provoked numerous wars, and there was almost constant conflict in Greece from 404 to 338.
No single city had the men and resources to achieve any sort of permanent hegemony over the city-states of Greece. All these conflicts did was to drain the resources of the city-states and make them vulnerable to the aggression of other Greek states with more centralized forms of government.
In the 400s the Greek polis system, exemplified by the highly successful Athenian polis, reached its height. But by the end of the century, both Athens and the polis had gone into decline. At its high point Athens probably came closer to achieving the theoretical objectives of the polis than any other city-state. In government it achieved a system in which all citizens participated on as equal a footing as was possible to achieve. Athens also became the first major Greek imperial power in the same period, extending her power at the expense of others. Many modern writers find the imperialism hard to reconcile with the achievements of Athens, but in fact they go together. The same loyalties and ambitions that made the Athenians excel in intellectual and political pursuits also made them want to dominate other cities.
It was this drive for supremacy that eventually brought Athens and the polis system to ruin. Historians sometimes criticize the Greeks for not finding a way to unite their diverse cities in a political system based on the polis. Why, they ask, couldn’t the Greeks build a Greece-wide state in which all Greeks participated as citizens on an equal basis? But this was not possible, if you look closer. In order for the Greeks to participate in government in the manner of the polis, the Greek state had to be small. In Greece, the right of a citizen did not stop with the right to vote. The citizen had to be able to participate directly in the polis, to sit in the assembly, and to hold office. In such a system, the number of citizens had to be limited.
