Credits to ~TagsMagilicuty for the image
A man who never knew fear, a man who was worth more than thousands of men, a man who entailed valor and boldness, a man who could persuade a large assembly with sweet words, and of course, the greatest warrior of Greece - Achilles, prince of the house of Peleus. These are just several of the great praises given to him based on the first books of Iliad.
Every man, wife and elder saw him as a great king, and the traits of such a king can be simplified into one strong statement: A king does what is best for his people. However, did the great Achilles possess that trait particularly in book 9?
To answer that question, let us assess his actions in the book.
King Agamemnon was already giving a great atonement to him which I think was the greatest peace offering made in the book. Moreover, he was actually accepting the wrongdoings he had committed, and he even swore an oath to him that he had never touched his wife. I think those are enough for Achilles maybe not to forgive Agamemnon at once, but to be in aid of his nation. However, he rejected the humble offer and apology. The eminence I saw in him slowly faded as I was reading the part where he was very ill-minded in decision making.
Credits to ~jonchan for the image
His decisions were very foot-in-mouth for a king and a champion like him. In that book, I saw Achilles as an angry man who was overruled by his emotions. He was still badly mourning for what King Agamemnon had done to him, and that was robbing his wife. As the post to which everyone leaned on, he did not think of the sake of his people; but instead, he only entertained the negative side of his ego and pride.
If he was a merchant, a shepherd, an ordinary person, I would be able to sympathize with him because he was badly wronged. However, he was not; his responsibility for the Achaians was unmatchable. His duty would always be his duty. The greatest warrior would always be the greatest warrior. Achilles would always be Achilles.
Credits to ~Merkaba998 for the image
Based on the assessment I've done, I conclude that Achilles didn't have the trait of a great king in book 9. On the other hand, there are still more books to come and I am pretty sure that this hero will redeem himself.
One lesson in life that we can learn from this is that the heart and the mind should always reach the balance for us to make right decisions in life. Sometimes when the mind overrules, one tends to forget the values that he should always carry with him. On the other hand, when the heart is in power, one tends to forget his duties, responsibilities and his main goal. Therefore, I say that when the mind is equal to the heart, and the heart is equal to the mind, right decisions in life will be made.
Credits to ~nikkixnervosa for the image