寰宇薈萃：從伯羅奔尼撒戰爭，印證權力失衡「修昔底德陷阱」

約瑟夫・奈伊：「雅典的勢力增長引起斯巴達恐懼，才使得戰爭不可避免。」

公元前四八零年，古希臘城邦國家雅典和斯巴達結盟，並聯手打敗波斯帝國。斯巴達是個保守、面向陸地的國家，戰勝後重心放在國內發展；雅典則是個商業、面向海洋的國家，經過半世紀發展成為強大帝國，並創建提洛同盟，即環愛琴海國家的同盟，共同防禦波斯人的威脅。

斯巴達則領導伯羅奔尼撒半島的鄰國組成防禦同盟。原先與雅典結盟並享受保護的國家，很快便須向雅典納稅。公元前四六一年，雅典帝國內部擴張及勢力增長，反對派勢力的出現導致戰爭爆發。雙方簽訂和約，結束持續約十六年的第一次伯羅奔尼撒戰爭，約定維持三十年和平。

公元前四三四年，位處邊緣的埃皮達姆努斯發生內戰，民主政治和寡頭政治的支持者分別就治理國家展開競爭。民主派向曾助埃皮達姆努斯建國的城邦國家基西拉求助不果，轉向科林斯求救，做法卻激怒基西拉。基西拉的艦隊重新佔領前殖民地埃皮達姆努斯，及擊敗科林斯軍隊。

科林斯遂向基西拉宣戰，害怕科林斯進攻的基西拉，因而向雅典求助，基西拉與科林斯均派使節到雅典。雅典不願破壞和平氛圍，惟擔心若科林斯征服基西拉並控制其強大海軍，力量對比將不利於雅典，故決定派出十艘船嚇唬科林斯，並下令「除非受到攻擊，否則不可動武」。

雅典的介入激怒科林斯，當基西拉將要戰敗時，科林斯同時向雅典海軍發動攻擊。雅典擔心科林斯為盟友帕提亞製造麻煩；若雅典進攻帕提亞，斯巴達表明幫助科林斯，結果在帕提亞發生叛亂後，雅典出兵鎮壓。埃皮達姆努斯紛爭「一石激起千層浪」，醞釀第二次伯羅奔尼撒戰爭。

雅典呼籲斯巴達保持中立；科林斯則提醒斯巴達不能無視雅典勢力，並鼓動斯巴達與雅典交戰。另一城邦國家墨加拉遭雅典斷絕商業聯繫，在認為雅典背棄和約下支持科林斯。斯巴達投票贊同向雅典開戰，擔心若不制約雅典，雅典可能控制整個希臘，期望維持希臘城邦權力平衡。

公元前四三一年，第二次伯羅奔尼撒戰爭爆發。交戰十年後雙方達成停戰協定，惟戰火很快再次燃燒。公元前四一三年，雅典派出兩支艦隊和步兵征服意大利南面的西西里島。該島有與斯巴達結盟的希臘殖民地，由於波斯希望雅典遭打擊，故金錢援助科林斯，結果雅典慘敗收場。

征戰西西里失敗後，雅典內部產生分裂。公元前四一一年，貴族派推翻民主派政權，四百名寡頭政治支持者統治雅典，使雅典從此一蹶不振。雅典翌年曾勝出一場海戰，但五年後斯巴達在海上戰勝雅典，後者更被迫求和。斯巴達要求雅典拆除防禦陸上強國進攻的城牆，雅典從此被擊垮。

名稱：哈佛最熱門的國際關係課：國際關係大師奈伊教你洞悉局勢，掌握先機，佈局未來！(Understanding Global Conflict and Cooperation: An Introduction to Theory and History)

作者：約瑟夫・奈伊、大衛・威爾許（張小明譯）

年份：2019

出版地：臺灣

出版社：商業周刊

類別：國際關係、社會科學

評分：6.5/10

Glosnap: Imbalance of Power, Peloponnesian War and Thucydides Trap

"What made the war inevitable was the growth of Athenian power and the fear this caused in Sparta." – Joseph S. Nye Jr.

In 480 BC, Athens and Sparta were allies to defeat the Persian Empire. Sparta was a conservative, land-oriented state that turned inward. Athens was a commercial, sea-oriented state that turned outward, which had 50 years of growth that led to the development of an Athenian empire. It formed the Delian League, an alliance of states around the Aegean Sea, for mutual protection against the Persians. Sparta organized its neighbors on the Peloponnesian Peninsula into a defensive alliance in turn.

Sooner or later, states that had joined Athens freely for protection against the Persians had to pay taxes to Athens. A war broke out in 461 due to the growing strength of Athens and the resistance of its growing empire. By 445, the first Peloponnesian War ended and was followed by a treaty that promised peace for 30 years. Greece enjoyed a period of stable peace before the second Peloponnesian War broke out.

In 434 BC, a civil war broke out in the small peripheral city-state of Epidamnus. The democrats fought with oligarchs over how to rule the country. The former one appealed to the city-state of Corcyra, which had helped establish Epidamnus, but were turned down. They turned to another city-state Corinth and Corinth decided to help. It angered the Corcyraeans, who sent a fleet to recapture their former colony and defeated the Corinthian fleet.

Corinth was outraged and declared war on Corcyra. Corcyra, fearing the attack from Corinth, turned to Athens for help. Both Corcyra and Corinth sent representatives to Athens. Athens was in a dilemma after listening to both sides. It did not want to break the truce that had lasted for a decade, But if the Corinthians conquered Corcyra and its large navy, the balance of power among the Greek states would tip against Athens.

Athens decided to become “a little bit involved”, by sending 10 ships to scare Corinth, under the instructions not to fight unless attacked. Yet, Corinth attacked Corcyra and Athens. Besides, Athens worried that Corinth would stir up problems in its ally Potidaea. Sparta promised to help Corinth if Athens attacked Potidaea. Athens sent forces to put the revolt of Potidaea down. Like a pebble that begins an avalanche, it triggered the second Peloponnesian War.

Athens appealed to Sparta to stay neutral. Corinth warned Sparta against failing to check the rising power of Athens and urged it to go to war. Another important city, Megara agreed with Corinth, whose trade had been banned by Athens. Spartans voted in favor of war in order to maintain the balance of power. According to Thucydides, Sparta were afraid that if Athens power was not checked, Athens might control the whole of Greece.

In 431 BC, the second war broke out. The early phase of the war came to a stalemate. A truce was declared after ten years, but it was fragile and war broke out again. In 413 BC, Athens sent two fleets and infantry to conquer Sicily, which had a number of Greek colonies allied to Sparta. At the same time, Sparta received additional money from the Persians, who were only too happy to see Athens’ failure. Athens was internally divided after the defeat in Sicily.

The oligarchs of Athens overthrew the democrats in 411 BC. 400 of them attempted to rule Athens. Athens never really recovered. An Athenian naval victory in 410 was followed 5 years later by a Spartan naval victory, and by 404 Athens was compelled to sue for peace. Sparta demanded that Athens pull down the long walls that protected it from attack by land-based powers. Athens’ power was broken.

Title: Understanding Global Conflict and Cooperation: An Introduction to Theory and History (10th Edition)

Author: Joseph S. Nye Jr., David A. Welch

Year: 2016

Region: USA

Publisher: Pearson

Genre: Social Science, International Relations

Score: 6.5/10

IMG: https://www.britannica.com/summary/Peloponnesian-War