Additionally, the ability of trains to haul large quantities of goods and significant numbers of people over long distances is the mode’s primary asset. Once the cars have been assembled or the passengers have boarded, trains can offer a high capacity service at a reasonable speed. “With containerized unit trains, economies of scale can be readily been achieved while road accounts for no such advantage. Each additional container being carried by road involves the same marginal cost increase, while for rail there is a declining marginal cost per additional container until the unit train size is reached. Passenger service is effective where population densities are high. Freight traffic is dominated by bulk cargo shipments, agricultural and industrial raw materials in particular. Rail transport is a ‘green’ system, in that its consumption of energy per unit load per km is lower than road modes.” (Dr. Jean-Paul Rodrigue, Dept. of Global Studies & Geography, Hofstra University, New York, USA)
In addition, high profile terrorist attacks on rail systems in Madrid, London, and Mumbai provide troubling illustration to persistent warnings that the U.S. public transportation system is a vulnerable target for terrorists. But passenger rail is not the only, and perhaps not even the gravest concern. Much of the 160,000 miles of railroad track in the United States transports freight, including highly toxic chemicals. These shipments often have minimal security, even though they pass through populated areas, endangering thousands of live. Though security professionals see trains as some of the likeliest terrorist targets, (P.J. Crowley), a homeland security expert at the Center for American Progress, explains: “On passenger rail, there’s a limit to what can be done.” Some experts believe existing precautions on most railroads already approach that limit, but Crowley suggests increasing police presence in stations and on trains could further diminish the risk of attack. The problem, he says, is that local governments usually don’t have the money to sustain such a force.
More importantly, Al Shabaab (Arabic for “the youth”), is an Islamic militant group that seeks to create an Islamic state in Somalia, formed in 2004 as the militant wing of the Islamic Courts Union. Although the group primarily targets Somali governmental officials and Ethiopian military forces, it has also conducted attacks against African Union Mission forces and international peacekeepers inside Somalia. Since the U.S. designated Al Shabaab a Foreign Terrorist Organization in October 2008, the group has also stated its intent to target Western interests both inside and outside Somalia. In April 2009, Al Shabaab fired mortar shells at a U.S.