The third week of April has been particularly calamitous in American history, as the Washington Post pointed out on Friday.

WASHINGTON – The third week of April has been particularly calamitous in American history, as The Washington Post pointed out on Friday.

As the nation was gripped by the massive manhunt for the remaining suspect in the Boston Marathon bombings, it’s worth taking a look back at some events that have also occurred during the same week in history.

April 19, 1775: The “shot heard ’round the world” marks the beginning of the Revolutionary War.

April 15, 1912: The Titanic sinks.

April 19, 1985: The Covenant, The Sword, and the Arm of the Lord siege occurs in Elijah, Missouri.

April 19, 1993: The Branch Davidian Massacre occurs in Waco, Texas.

April 19, 1995: The Oklahoma City bombing occurs.

April 20, 1999: The Columbine Massacre occurs.

April 16, 2007: The Virginia Tech shootings occur.

April 20, 2010: The BP Oil Spill

April attracts certain kinds of attacks and incidents, partly for political reasons and partly because of the weather.

Joseph Young, an assistant professor at American University’s School of Public Affairs, says the nationalistic focus surrounding Patriots’ Day attracts persons or groups who may be hoping to make a political statement.

“Symbolically, it’s a time that’s important for patriot-style movements, but I think that’s unrelated to this event as far as we know right now,” he said.

Though the Boston Marathon bombing has not been tied to a political statement so far, Young says the weather can also play a factor in April. Based on a theory of criminology, there needs to be a motivated offender, a lack of a capable guardian and a victim in order for a crime to occur.

Based on this theory, Young says the suspects in the Boston bombing and the difficulty of guarding a large marathon contributed to the crime, but the warmer weather may have also enticed more people to come out and watch, creating more potential victims.

“More likely, this is a story about (the suspects) having easy access to a marathon, a marathon being an event that’s really difficult to police,” Young says. “It’s really hard to stop any kind of violence that may occur with this kind of event.”

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