Jihad means to struggle or battle. While many Muslims and Western liberals insist the term is used primarily in a non-violent sense, this is misleading. The world view of Islam is based upon an us-versus-them model. Islam is doctrinally in a state of perpetual war against non-Muslims, even when a truce has been signed. This constant state of war-readiness of Islam is a key to understand their view of the world. Daniel Pipes explains:
Jihad is “holy war.” Or, more precisely: It means the legal, compulsory, communal effort to expand the territories ruled by Muslims at the expense of territories ruled by non-Muslims.
The purpose of jihad, in other words, is not directly to spread the Islamic faith but to extend sovereign Muslim power (faith, of course, often follows the flag). Jihad is thus unabashedly offensive in nature, with the eventual goal of achieving Muslim dominion over the entire globe.
Jihad in the sense of territorial expansion has always been a central aspect of Muslim life. That’s how Muslims came to rule much of the Arabian Peninsula by the time of the Prophet Muhammad’s death in 632. It’s how, a century later, Muslims had conquered a region from Afghanistan to Spain. Subsequently, jihad spurred and justified Muslim conquests of such territories as India, Sudan, Anatolia, and the Balkans.