Let's begin with the basic story:
Sunan an-Nasa'i 4029--Anas bin Malik narrated that a group of eighty people from Ukl came to the Prophet, but the climate of Al-Madinah did not suit them and they fell sick. They complained about that to the Messenger of Allah and he said: "Why don't you go out with our herdsmen and drink the milk and urine of the camels?" They said: "Yes (we will do that)." They went out and drank some of the (camels') milk and urine, and they recovered. Then they killed the herdsmen of the Messenger of Allah, so he sent (men after them) and they caught them and brought them back. He had their hands and feet cut off and branded their eyes, and left them in the sun to die.
While this Hadith doesn't clearly state the reason for the punishment, the following Hadith does:
Sunan an-Nasa'i 4040--It was narrated that Anas bin Malik said: "Some Bedouin from Uraynah came to the Prophet of Allah and accepted Islam, but the climate of Al-Madinah did not suit them; their skin turned yellow and their bellies became swollen. The Prophet of Allah sent them to some milk camels of his and told them to drink their milk and urine until they recovered. Then they killed their herdsmen and drove off the camels. The Prophet of Allah sent (men) after them and they were brought back, then he had their hands and feet cut off, and their eyes were branded." The Commander of the Believers, Abdul-Malik, said to Anas, when he was narrating this Hadith: "Was that (punishment) for Kufr or for sin?" He said: "For Kufr."
So we can see that the punishment was not for attacking the herdsman, but for leaving Islam! But wait, there's more:
Sunan an-Nasa'i 4042--It was narrated that Aishah said: "Some people raided the milk camels of the Messenger of Allah. He caught them and had their hands and feet cut off and their eyes gouged out."
Here it seems that the men were tortured and mutilated simply because they dared raid Muhammad's camels. But we have yet another reason:
Sunan an-Nasa'i 4048--It was narrated that Anas said: "The Prophet only had the eyes of those people gouged out, because they had gouged out the eyes of the herdsmen."
Bassam, of course will go with this reason, since it seems the least unjust to him. The problem, of course, is that even Allah believed that Muhammad's punishment was unjust:
Sunan an-Nasa'i 4047--It was narrated from Abu Az-Zinad that the Messenger of Allah had the (hands and feet) of those who drove off his camels cut off, and their eyes gouged out with fire. Allah rebuked him for that, and Allah, Most High, revealed the entire verse: "The recompense of those who wage war against Allah and His Messenger."
Why bother defending a man so brutal that even Allah (certainly no stranger to brutal punishments) must rebuke him? (Notice that the only reason given for the punishment in this Hadith is that the men drove off Muhammad's camels.)
*****NOTE: BE CAREFUL IF YOU WANT TO AGREE WITH ALLAH AND SAY THAT MUHAMMAD WAS WRONG FOR TORTURING, MUTILATING, AND EXECUTING THESE MEN. IF YOU DO, YOU'RE SURE TO GET THE STANDARD MUSLIM RESPONSE: "BUT THE BIBLE . . ." (AS IF THIS ANSWERS THE OBJECTION AND REMOVES THE BRUTALITY!)*****