During the four years since 9/11 I've received numerous letters like this recent one: "What can be done to help educate people on the dangers that radical Islam poses to Western Civilization? I don't think this ideological conflict will go away."
No, it won't. It is likely to be for the first half of the 21st century what the Cold War was for the last half of the 20th, a long subtle struggle with occasional days of fire. How to educate folks? Use of all media will be needed, but here's a list of books I've found useful.
First, to understand radical Islam some sense of basic Islam is essential, and that starts with the Quran. Muslims insist that unless you've read it in Arabic you haven't read it: Maybe so, but in theology as well as in horseshoes leaners are better than nothing, so I'd recommend either reading a translation on the internet or buying the new Quran translation by M.A.S. Abdel Haleem that came out last year in paperback from Oxford University Press.
Some scholars now ask tough questions about the Quran's historicity: As I type with one hand I'm holding in the other John Wansbrough's Quranic Studies (Prometheus Books [PB], 2004) and Ibn Warraq's The Origins of the Koran (PB, 1998). Mr. Warraq left Islam after coming to believe the Muhammad story was a sham, and his books include Why I Am Not a Muslim (PB, 1995), The Quest for the Historical Muhammad (PB, 2000), and Leaving Islam: Apostates Speak Out (PB, 2003).
Second in importance within Islam after the Quran are the Hadith, massive works delineating how Muhammad supposedly dressed, ate, ingested and excreted food and drink, and so forth. Many Hadith collections are available online, but Ram Swarup's critical and succinct summary, Understanding the Hadith: The Sacred Traditions of Islam (PB, 2002), is a place to start. Crossroads to Islam by Yehuda Nevo and Judith Koren (PB, 2003) also gives useful insights into Muslim origins.
To understand how Islam affects non-Muslims (called "dhimmis"), read three books by historian Bat Ye'or. On top of my right foot now are The Dhimmi: Jews and Christians under Islam (Fairleigh Dickinson U. Press [FDU], 1985), The Decline of Eastern Christianity under Islam (FDU, 1996), and Islam and Dhimmitude (FDU, 2002). A book edited by Robert Spencer, The Myth of Islamic Tolerance (PB, 2004), includes many useful short essays on dhimmitude.
Islam at the Crossroads by Paul Marshall, Roberta Green, and Lela Gilbert (Baker, 2002) and Islam Unveiled by Robert Spencer (Encounter, 2002) provide succinct overviews of past and present. It's also good to read material from the Islamophile side, so sitting on my left toes are Karen Armstrong's Muhammad: A Biography of the Prophet (HarperCollins, 1993), Malise Ruthven's Islam (Oxford, 1997), Richard Fletcher's The Cross and the Crescent (Penguin, 2003), and Reza Aslan's new No god but God: The Origins, Evolution, and Future of Islam (Random House, 2005).
Now, with the foundations laid, we can proceed to five books about radical Islam that I'm balancing on my knees. Sword of Islam by John F. Murphy Jr. (PB, 2002) and Onward Muslim Soldiers (Regnery, 2003) by Robert Spencer sweep through the history. Paul Marshall's Radical Islam's Rules (Rowman & Littlefield, 2005) shows how Shariah law works in many Muslim-dominated countries. Daniel Pipes' Militant Islam Reaches America (Norton, 2002) and David Horowitz's Unholy Alliance: Radical Islam and the American Left (Regnery, 2004) tell of the threat to the good old, still-asleep USA.
Those books suggest geopolitical responses, but in the long run theological responses are more important, so I'd recommend six others from recent years: Answering Islam by Norman Geisler and Abdul Saleeb (Baker, 2002), Muslims and Christians at the Table by Bruce McDowell and Anees Zaka (Presbyterian & Reformed [P&R], 1999), The Truth about Islam by Anees Zaka and Diane Coleman (P&R, 2004), What You Need to Know about Islam & Muslims by George W. Braswell Jr. (Broadman & Holman, 2000), and two by Edmir Fethi Caner and Ergun Mehmet Caner, Unveiling Islam and More Than a Prophet (Kregel, 2002 and 2003).
The William Carey Library has published still-useful books such as Christian Mission to Muslims (1977) and A Christian Approach to Muslims (1979). Finally, many people found WORLD's post-Sept. 11 overview of Islam helpful.