We still don't know who caused the bombings that killed three people and wounded dozens more at the finish line of the Boston Marathon on Monday afternoon. It might have been a lone wolf or an organized group of people. And perhaps more importantly, we don't know why. But we are a nation familiar with terror.
From emergency personnel to innocent bystanders, there's a certain degree of familiarity with this scenario. And when it comes to authorities, that's no accident. They have planned for and practiced responding to attacks of all kinds post-9/11 in a way that would have seemed wildly paranoid before thousands lost their lives in the terrorist attacks more than a decade ago.
Now, the following measures, many of which were used in Boston and put in place in response to 9/11, represent a new normal.
Pre-Race Measures: Anthony Roman, a security expert, told The New York Times that for major events in large cities, police would now examine the entire race route before the start, weld manhole covers shut, place snipers and helicopters overhead, and employ analytic cameras.
Homeland Security: Homeland security advisers briefed the president shortly after the blasts occurred. The Department of Homeland Security was created in November 2002 after Congress passed the Homeland Security Act. The department replaced the Office of Homeland Security, which had been set up just days after terrorists attacked the twin towers in New York City.
No-Fly Zone: Federal Aviation Administration officials created a no-fly zone over Boston following the bombings. They instructed flights bound for Boston's Logan International Airport to hold at other airports.
Raised Maritime Security: The New York Times reported that the maritime security level in Boston was raised from level one to level two; with level three being the highest possibility. According to the U.S. Coast Guard, level two is when additional security measures are added following a "heightened risk of a transportation security incident."
National Ramifications: Officials in New York and Washington, D.C. increased security. The Washington Post reported that helicopters patrolled near the new World Trade Center. The White House stepped up security as did the Washington Metropolitan Area Transit Authority.
Social Media: Everyone from authorities to civilians to lawmakers has turned to social media to send and receive information when these situations arise around the world. In this case, the Boston Police department used Twitter to tell people to stay away from Copley Square. A Google Doc was also created to help reunite people, and another where locals have offered up guest rooms and free rides. But inaccurate information still spreads, perhaps even more now than on 9/11 with the rise of social networking sites like Twitter. Reports that police shut down cellphone service in the area circulated widely before sites like Mashable debunked them.