President Obama visited Waco, Texas, on Thursday day to take part in a memorial for those killed in the fertilizer plant explosion in West, Texas, last week.
While President Obama's time in office has not been defined by terrorist attacks, incidents like the one in Boston have been a regular, painful through line of his presidency. And the Obama administration has been on a steady learning curve when it comes to how to handle its public response.
Law enforcement officials have been given high marks for their response to the bombings at the Boston Marathon. But at the same time, questions are being raised about the coordination among federal agencies handling intelligence about the suspects in the months before the attack.
The Boston Police Department tweeted photos of bombing suspect Dzhokhar Tsarnaev and later announced his capture via social media. As the number of Twitter users grows, police forces face new opportunities and challenges in using social media for communicating with the public.
It quickly became clear that the "news" was not true. There had been no explosions at the White House and President Obama was fine. But a message on the wire service's Twitter account rattled investors.
Under current laws, if a background check shows your name is on the national terror watch list, you can still purchase a gun. Government data show that people on terrorism watch lists were able to buy guns or explosives after a background check more than 1,300 times between 2004 and 2010.
An overhaul of the country's immigration laws by Congress is not yet a done deal. One change already in place, though, is a program that prevents young adults brought to the country illegally as children from being deported. Still, the majority of the eligible 1.7 million have yet to apply.
The federal probe of poisoned letters sent to President Obama and others has taken an abrupt change of course. On Tuesday, U.S. prosecutors dropped charges against the Mississippi man first arrested in the case. FBI agents have taken their search for clues to another man's house in Tupelo.
In Boston on Tuesday, residents and business owners on Boylston Street were allowed to return for the first time since last week's bombings. They returned to stores with windows blown out, restaurants with the remains of uneaten meals still sitting on tables and barricades to keep the public away from the scene.
The Americans and the Europeans have different approaches to horse racing, and one key split is over the question of doping. While many drugs are allowed in the U.S., they are banned in European racing.