Ammonium nitrate in the news and over the years

Ammonium nitrate finds its way into any good discussion of nitrogen chemistry.  This compound, used as a fertilizer in many cases, also can be used as an explosive.  A former student of mine had a parent that worked at a company that mixed ammonium nitrate and oil to produce a blasting material for construction purposes. The oil adds more reducing power to the redox reactions involved in the explosions, increasing their potency. Unfortunately, many terrorists have produced a similar mixture and used it in events such as the World Trade Center bombing in 1993 and the Alfred P. Murrah federal building bombing in Oklahoma City in 1995.  Ammonium nitrate can explode to do plenty of damage without oil, too.  One example is the  explosion at the fertilizer plant in West, TX (which is located in the eastern half of Texas), see:  http://www.cnn.com/2013/04/19/us/texas-explosion/index.html?hpt=hp_inthenews.  Previous to that there was an explosion at a fertilizer plant in France in 2001.  And of course there is the Texas City disaster in 1947, in which two ships loaded with ammonium nitrate exploded and did extensive damage.  I visited Texas City in 2011 and stopped by their city museum and other sites.  They featured, among other exhibits, information about the disaster.  Some pictures of that visit are featured in this post.