"but if they turn their backs, then seize them and kill them wheresoever ye find them" is not a justification for defensive measures. Indeed, the Koran is not a religious document; it is a blueprint for murder.
You should read it, or at least enough of it to get a sense of where it's headed:
The Harvard Classics Translations of 1909-1914
nicely formatted by the folks at bartleby.comJ.M. Rodwell's 1957 Translationhttp://www.bartleby.com/45/5/
Project Gutenberg
(widely mirrored; these are FTP (not HTTP) mirrors at UNC-Chapel Hill's ibiblio.org)ftp://ibiblio.org/pub/docs/books/gutenberg/etext01/koran10.txt (2000)ftp://ibiblio.org/pub/docs/books/gutenberg/etext02/koran10a.txt (2001)
Maulana Muhammad Ali's 1951 Translation (Second Edition)http://www.muslim.org/cont-islam.htm Rashad Khalifa's 2000 Translation (Second Edition)
http://www.submission.org/quran/