Osama bin Laden issues a fatwa entitled 'Declaration of War against the Americans Occupying the Land of the Two Holy Places.' According to bin Laden, it's the "legitimate right" of Saudis to strike at the 5,000 American servicemen stationed in Saudi Arabia.
Osama bin Laden writes:
"It should not be hidden from you that the people of Islam had suffered from aggression, iniquity and injustice imposed on them by the Zionist-Crusaders alliance and their collaborators; to the extent that the Muslims blood became the cheapest and their wealth as loot in the hands of the enemies.
... It is essential to hit the main enemy who divided the Ummah into small and little countries and pushed it, for the last few decades, into a state of confusion. ...
It is out of date and no longer acceptable to claim that the presence of the crusaders is necessity and only a temporary measures to protect the land of the two Holy Places. Especially when the civil and the military infrastructures of Iraq were savagely destroyed showing the depth of the Zionist-Crusaders hatred to the Muslims and their children, and the rejection of the idea of replacing the crusaders forces by an Islamic force composed of the sons of the country and other Muslim people. ...
Terrorizing you, while you are carrying arms on our land, is a legitimate and morally demanded duty. It is a legitimate right well known to all humans and other creatures.
Your example and our example is like a snake which entered into a house of a man and got killed by him. The coward is the one who lets you walk, while carrying arms, freely on his land and provides you with peace and security."