Explainer

Cupcake Wars

Can you really make a bomb out of a pastry?

How much frosting would a cupcake bomb need?
How much frosting would a cupcake bomb need?

Photograph by iStockphoto/Thinkstock.

TSA agents reportedly confiscated a traveler’s cupcake as she passed through security at Las Vegas-McCarran International Airport last Wednesday. The security officers determined that the frosting might have been an explosive gel. Could someone really make a cupcake bomb?

Possibly, but it would be extremely weak. Several types of liquid explosives can be mixed into a paste-like form and combined with colorant to look something like cupcake frosting. A cupcake wouldn’t be a particularly effective weapon of terror, though. Attackers would likely need several times the weight of frosting on even the most decadent cupcake to threaten a commercial airliner, and it would have to be tightly packed in a container rather than sitting atop a pastry. If a traveler had a full-sheet birthday cake, the TSA would have a somewhat stronger case for confiscation. (The agency is investigating the circumstances surrounding the cupcake incident but has publicly stated that passengers usually are permitted to carry cakes and cupcakes through security checkpoints.)

Liquid explosives come in a variety of forms. The best known is nitroglycerine, which is syrupy at room temperature and hardens to a gel when chilled. It could be spreadable at the right temperature, but agitation alone can set it off, making it difficult to carry onto a plane.

Liquid explosives used in terror attacks are more often a combination of ingredients. In 1995, for example, Timothy McVeigh and his accomplices used ammonium nitrate and nitromethane to destroy the Alfred P. Murrah Federal Building. That mixture and others like it could be combined with adulterants at the right temperature to look like a frosting, but the couple of ounces that would fit on a cupcake aren’t likely to generate a dangerous explosion.

One shouldn’t be too quick to dismiss the danger of pantry staples. The bombers who attacked London’s public transit system in 2005 used a mixture of peroxide and ordinary flour. (Chapati flour in this case, but regular all-purpose flour or any starchy powder would have done the trick.) This recipe could also take on the consistency of frosting if combined in the right ratio, but it would make a terrible choice for airplane bombers. The reaction begins almost immediately upon mixing, resulting in a frothing, steaming mass that would certainly catch the attention of security screeners. It would also have to be detonated in a matter of minutes, and every terrorist knows you have to arrive at the airport an hour before takeoff.

The incident at Las Vegas airport is the second terrorism-related cupcake story of the year. In the spring, agents from MI6, the intelligence agency for the United Kingdom, hacked into al-Qaida’s online magazine Inspire and replaced the bomb-making instructions with cupcake recipes from The Ellen DeGeneres Show.

Got a question about today’s news? Ask the Explainer.

Explainer thanks John Goodpaster of Indiana University-Purdue University Indianapolis.