Ask the question of most any observer, and the answer would include catchphrases like “global marketplace,” “global village,” or “globalization.” Modern communications and transportation connect people as never before—businesses enjoy broader markets for their goods and services, manufacturing facilities and jobs are located far from the offices of the companies that market them, and people of many nationalities, races, and religions have more and more contact with one another every day, for business and pleasure. Some observers worry that this contact will blur rich cultural differences, diluting diversity; others say that globalization will bring tolerance and increase understanding. Whatever the case, we are living our lives on a global stage: The things we buy and use are as likely to carry “Made in china” or “Made in Mexico” labels as they are any other; people continents away talk to each other not just over the telephone, but via cell phones, instant messages, e-mail, and Internet chat rooms; we have an international forum—the Internet—for buying, selling, and publishing; and we can get almost anywhere in the world with all due haste. Everything travels faster today, including ideas.

The upsides are many. Modern communications and transportation made it possible, for example, for the world to mobilize aid to victims of the Southeast Asian tsunami of December 2004. But there are downsides as well. Critics say globalization is fueling the exploitation of workers in developing nations, contributing to a modern slave trade, rapidly depleting resources, and wiping out environmental diversity. These are some of the reasons protesters have demonstrated outside meetings of the World Trade Organization, why some people opposed the North American Free Trade Agreement (NAFTA) and oppose the pending CAFTA (Central American Free Trade Agreement), and why many people dislike that American popular culture is marketed around the world. The problem could be distilled to this: diversity versus homogeneity. And the resulting culture clashes are not restricted to the realm of scholarly thought; they are making headline news. The enemy is no longer the strong-armed, nuclear-fortified, absolutist government of the cold War era (though, as of mid-2005, North Korea remained a serious concern); the enemy, as the U.S. State Department reminds us, is any group of individuals with extreme views.

Who is the enemy of the day? Terrorists. News stories reinforce that this catch-all term does not only include the 9/11 hijackers and their al Qaeda associates, the Madrid and London train bombers, and suicide bombers in Gaza, but antigovernment extremists who blew up a federal building in Oklahoma city, a still-unknown distributor of deadly anthrax, and animal rights activists who routinely damage property to make a point. Terrorism is a decades- (some might argue, centuries-) old problem. Remember Birmingham, Alabama’s Sixteenth Street Baptist Church, bombed in 1963 by white supremacists during Sunday services. Remember the 1972 summer Olympics in Munich, when the Arab terrorist group Black September killed 11 Israeli athletes held captive in the Olympic village. Remember the October 1985 hijacking of the Achille Lauro cruise ship by members of the Palestinian Liberation Front, who killed a wheelchair-bound American Jew. Remember the December 1988 bombing of Pan Am Flight 103, which came down in Lockerbie, Scotland, claiming 270 lives. The list is long and growing.

The shocking events of September 11, 2001, centered the world’s attention on the problem of well-financed terrorist networks that can turn the freedoms of democracy against civilians—and who are feared to have in their possession or access to powerful weapons of mass destruction (WMD). The events of that day launched what the U.S. government calls the Global War on Terrorism, a long battle that even the president acknowledged may not be winnable in a traditional sense. This is a new kind of war, fought not against a nation, but against anarchists halfway around the world, and in our midst. Globalization and terrorism are the twin concerns of the modern era.