There are many verses in the Quran which give permission for war. But this is also the case with the holy books of other religions. For example, in the Bible Jesus says: "I did not come to bring peace but a sword." (Matthew 10:34). In the Gita, Krishna urges Arjun in these words: "O Arjun, go ahead and fight." In these scriptures too there is an injunction to engage in battle. When you study different religions, you will realize that they do speak about war. Thus you will realize that every religion is basically a religion of love, compassion and peace. However, as an exception, every religion allows for war for the purpose of defense.