"Why on earth are these animals doing this?"
Zawahiri (Osama's #2) is a leader of Egyptian Islamic Jihad. He was involved in the assassination of Anwar Sadat and was imprisoned by Mubarak for a while. Zawahiri hates the Egyptian government; and Mubarak and his government have been a target for many years. (There have been many plots to murder Mubarak - most notably in 1995 in New York.) This is also why al Qaeda murdered that poor Egyptian ambassador to Iraq recently. Zawahiri wanted him dead.
Al Qaeda wants to bring down the Egyptian government by any means possible - e.g., by destroying the tourist business; and to torpedo any arrangement Egypt makes with Israel to maintain order in Gaza. Al Qaeda would like to be free to move into the Sinai area and Gaza (which is strategically located on the Mediterranean) to use as a base for operations.
Zawahiri (Osama's #2) is a leader of Egyptian Islamic Jihad. He was involved in the assassination of Anwar Sadat and was imprisoned by Mubarak for a while. Zawahiri hates the Egyptian government; and Mubarak and his government have been a target for many years.
You're correct, these people(?) originally started out trying to bring down the governments in the mid east. The turned to fighting us (The West) because 1. these governments while not very good at governing were very good at staying in power. 2 we supported these governments.
Example Khomeini's hatered for America stems from our support of the Shah.
And of course our support for Israel figures into it also.