In the book "The Odyssey," how does Odysseus show cruelty ?

Odysseus shows cruely several times, but the most marked is when he kills the suitors. Even Homer says so. Look at Book XXII:

Odysseus answered, “Telemachus and I will hold these suitors in check, no matter what they do; go back both of you and bind Melanthius' hands and feet behind him. Throw him into the store room and make the door fast behind you; then fasten a noose about his body, and string him close up to the rafters from a high bearing-post, that he may linger on in an agony.”

Wanting someone to be in agony sounds cruel, and Homer even says, a few lines later "There, then, they left him in very cruel bondage..." calling the act cruel.

He does other cruel things, but that stands out. Yes, the suitors robbed him--but kill them all? And to torture?