It's an easy cop-out, pure propaganda, to say they hated us for our freedoms. They hate us still for our foreign policy towards them, decades of propping up brutal dictators, stealing their natural resources, and using their lands for our military bases.

Actually, I should have added to this post.

Since 9/11, I have been reading about Islam. This mass murder was commanded by Islam. As Jesus was all "Feed the poor! Turn the other cheek!" Mohammed was a tribal, warring sociopath who raped, murdered, looted and committed other heinous acts. The Quran commands Muslims to convert or slaughter the infidel, and the later passages calling for that "abrogate" the earlier ones that are more "let's all be nice to each other."

This is a crime created by Islam, make no mistake.

The motives are writ large in the Quran. Sura 9:5, for example. And modern Muslims who murder for religion are just following the dictates of their religion. From that Wiki link:

Al-Qaeda released a Fatwa, stating "We -- with God's help -- call on every Muslim who believes in God and wishes to be rewarded to comply with God's order to kill the Americans and plunder their money wherever and whenever they find it.

Example:

http://www.thereligionofpeace.com/Quran/020-stealing.htm

Question: Are Muslims permitted to steal from others?

Summary Answer:
Muslims may not steal from each other. In fact, Muhammad had people's hands cut off for that. But the same is not true of unbelievers. Property rights for them exist only at the discretion of their Muslim rulers. Non-submissive infidels frequently had their property stolen from them by Muhammad's warriors, which sometimes included wives and children.

More from that link:

Stealing from Unbelievers Permitted if Needed Ibn Ishaq (764) - As for taking from unbelievers, perhaps the most illuminating example among many comes from the aftermath of the battle against the Khaybar as recorded by Muhammad's earliest biographer. The Khaybar were a peaceful community of Jewish farmers who did not even know they were at war until Muhammad led his men against their town one morning, taking them by surprise and handily defeating them. Not only did Muhammad take much of the town's possessions and land, but he actually had the tribe's treasurer, a man named Kinana, tortured until he gave up the location of hidden treasure. Muhammad then beheaded the man and "married" his traumatized widow, Safiyya (who passed through the hands of one of his lieutenant's first due to the luck of the draw). Bukhari (44:668) - "We were in the company of the Prophet at Dhul-Hulaifa. The people felt hungry and captured some camels and sheep (as booty)..." Muhammad said that Allah would always provide sustenance for those who believe in him. Stealing from non-Muslims was a legitimate means of fulfilling Allah's promise. Ahmad 4869 (also found in the original Hadith of Bukhari and Sahih al Jaami' As Sagheer 2828) - It is mentioned from Ibn ‘Umar from the Prophet, may Allah bless him and grant him peace, “I have been raised between the hands of the Hour with the sword, until Allah the Exalted is worshipped alone with no associates. He has provided sustenance from beneath the shadow of spears and has decreed humiliation and belittlement for those who oppose my order.” Muhammad's livelihood is found in the property of those who disobey him - to be seized by force if necessary. 'Humilition" refer to the jizya that non-Muslims are supposed to pay Muslims by the mere fact of their unbelief.

Another, same link:

Consider this remarkable excerpt from a recent televised sermon by Abu Ishak al Huweini: "We are at a time of Jihad; Jihad for the sake of Allah is a pleasure, a true pleasure. Mohammed’s followers used to compete to do it. The reason we are poor now is because we have abandoned jihad. If only we can conduct a jihadist invasion at least once a year or if possible twice or three times, then many people on Earth would become Muslims. And if anyone prevents our dawa or stands in our way, then we must kill them or take as hostage and confiscate their wealth, women and children. Such battles will fill the pockets of the Mujahid who can return home with 3 or 4 slaves, 3 or 4 women and 3 or 4 children. This can be a profitable business if you multiply each head by 300 or 400 dirham,. This can be like financial shelter whereby a jihadist, in time of financial need, can always sell one of these heads (meaning slavery). No one can make that much money in one deal (from hard work) even if a Muslim goes to the West to work or do trade. In time of need, that is a good resource for profit."