What most people don't know is that the Koran specifically states that it is ok to lie and cheat especially to the infidel as long as it benefits Islam.
http://www.islamreview.com/articles/lyingprint.htm
Arabic: ومكروا ومكر الله والله خير الماكرين
Transliteration: Wamakaroo wamakara Allahu waAllahu khayru almakireena
Literal: And they cheated/deceived and God cheated/deceived, and God (is) the best (of) the cheaters/deceivers.[1]
Qur'an Text/Transliteration 3:54
"Allah will not call you to account for thoughtlessness (vain) in your oaths, but for the intention in your hearts; and He is Oft-forgiving, Most Forbearing." Surah 2:225