Islam makes it incumbent on all adult males, provided they are not disabled or incapacitated, to prepare themselves for the conquest of [other] countries so that the writ of Islam is obeyed in every country in the world. . . . But those who study Islamic Holy War will understand why Islam wants to conquer the whole world. . . . Those who know nothing of Islam pretend that Islam counsels against war. Those [who say this] are witless. Islam says: Kill all the unbelievers just as they would kill you all! Does this mean that Muslims should sit back until they are devoured by [the unbelievers]? Islam says: Kill them [the non-Muslims], put them to the sword and scatter [their armies]. Does this mean sitting back until [non-Muslims] overcome us? Islam says: Kill in the service of Allah those who may want to kill you! Does this mean that we should surrender [to the enemy]? Islam says: Whatever good there is exists thanks to the sword and in the shadow of the sword! People cannot be made obedient except with the sword! The sword is the key to Paradise, which can be opened only for the Holy Warriors! There are hundreds of other [Qur'anic] psalms and Hadiths [sayings of the Prophet] urging Muslims to value war and to fight. Does all this mean that Islam is a religion that prevents men from waging war? I spit upon those foolish souls who make such a claim.
Ruhollah Khomeini