Much remains unknown about Umar Farouk Abdulmutallab, the alleged attacker of Northwest Airlines flight 253. Apparently, during questioning he identified himself as a member of al-Qaida, but this has yet to be confirmed. It also has been reported widely that he was on a US terrorism watch list, but not on a no-fly list. Questions have been raised regarding security screening and about the improvised explosive device he used in his failed attack. The answers to these and other questions about the attacker, his motives and the events that led to his arrest in Detroit should become clear in the coming days and weeks. Other facets of this incident are immediately apparent and are consistent with long-standing understandings about terrorism and its perpetrators, including Abdulmutallab's reportedly well-to-do background and Western university education, the symbolic timing of attacking on Christmas and the choice of a commercial aviation target. ATTEMPTS TO bring dangerous materials aboard aircraft continue (illustrated most notably by the UK-based transatlantic bombing plot in 2006, the same year the US Transportation Security Administration intercepted more than 1.6 million knives at security checkpoints), and two recent developments pose particular challenges for airport security officials. First, the use of less detectable weapons technologies (i.e., liquids and powders instead of metals) makes it appear increasingly likely that determined terrorists can board with their hazardous cargo. Second, the potential for suicide attacks undermines some security measures, such as matching checked luggage to on-board passengers. The TSA claims that it screens 100 percent of checked baggage using explosive detection systems. Undoubtedly this claim will be reviewed, in the US and elsewhere, in the wake of Friday's abortive attack. In broader terms, even before the attempted attack on Christmas Day, 2009 has witnessed a significant number of planned, attempted and successful terrorist attacks in the US. Among them: the May 20 attempted bombing of two New York synagogues and plan to shoot down a military aircraft at an air force base elsewhere in New York; the June 1 shooting attack at an army recruiting office in Little Rock, Arkansas, that left one soldier dead and another wounded; the alleged bomb plot by Najibullah Zazi, arrested by FBI agents on September 19; the similar, though apparently unrelated, attempts to bomb federal and commercial office buildings in Dallas, Texas, and Springfield, Illinois, in late September; the November 5 active shooting attack by Maj. Nidal Malik Hasan at Fort Hood, Texas, that left 13 dead and 32 wounded. THIS STREAM of activity appears to represent an increase over recent years. Why is this the case, especially in light of the September Pew Global Attitudes Project report that worldwide support for Osama bin Laden (and by implication, for the ideology he represents) is decreasing? First, such surveys, though encouraging, can be misleading. While public support is essential for the maintenance of terrorist campaigns, typically only a small number of people are responsible for most terrorist activity. Indeed, even if Abdulmutallab turns out to be an al-Qaida-inspired but unaffiliated "lone wolf," it will demonstrate yet again that individual terrorists can make a global impact. (Incidentally, the Pew survey showed that support for bin Laden was decreasing in eight of nine Muslim publics surveyed. The only place where support was found to have increased? Nigeria.) Second, and perhaps most importantly, the terrorists involved in the attacks listed above specifically mentioned being motivated by current American military activity around the world, which they perceived as targeting Muslims. Despite the change in administration and the subsequent improvement of America's image around the world, US efforts to combat terrorism in Iraq and Afghanistan might be creating more terrorists than they are defeating or dissuading. This is just the latest manifestation of the considerable challenge terrorism presents to governments around the world: How can they use the full spectrum of counterterrorism tools (e.g., legal, public diplomacy, military) to meet this threat without making things worse? The writer is a research fellow at the Institute for National Security Studies at Tel Aviv University.