On Tuesday, Americans will mark the one year anniversary of the Boston Marathon bombings with ceremonies and memorials to honor and remember the three innocent victims killed and more than 260 others injured, many severely when pressure cooker bombs detonated near the finish line on April 15, 2013.
The 118th Annual Boston Marathon is scheduled to begin on April 21, 2014, the focus will shift to added security measures employed for the first event since the bombings, the worst terrorist attack on U.S. soil since the September 11, 2001, terrorist attacks.
Worldwide, terrorists groups have historically chosen symbolic targets on particular anniversaries or commemorative dates. Nationalist groups may strike to commemorate battles won or lost during a conventional struggle, whereas religious groups may strike to mark particularly appropriate observances.
In the United States, there have been a number of significant violent events that have occurred in mid-April, close to the April 19, 1993, anniversary of the raid on the compound of the Branch Dravidian's in Waco, Texas.
On the second anniversary of the Waco siege, Timothy McVeigh bombed the Alfred P. Murray Federal Building in the 1995 Oklahoma City bombing which killed 168 innocent victims, including children. Friends of McVeigh said he chose April 19 because he wanted payback for the deaths at Waco that he blamed on the federal government. Second, April 19, 1775, is the anniversary of the start of the American Revolution, the day the opening shot was fired in Concord/Lexington, known as Liberty Day.
Preventative measures that may prevent future terrorist attacks on soft targets favored by terrorists groups or "lone wolf" sympathizers that the U.S. Department of Homeland Security warns of, will largely rely on an alert public's ability to save themselves and their neighbors.