"The hierarchy was just figuring out what to do. They knew it was going to be a long-term thing, so they didn't want to rush to any one direction or another," he said.
This marked what Dunphy saw as a shift from preparations for their ratings and certification evaluations to "protection mode."
"The department has grown incredibly, and it's focused its attention more so to terrorist activity. So it's focused more on protection than anything else, and that is what they pay us for," he said.
Both Thompson and Dunphy stayed late that day, guarding the Capitol against a threat that hadn't yet completely taken shape. And both continued to come to work in the following weeks, serving long hours, working extra shifts, adjusting to the new normal.
"It never really occurred to me to say, 'Hey, I protected and served this day, but I think I'm done now.' That's not really the commitment I signed up for," Thompson said.
Former Sen. Scott Brown, R-Mass., candidate for U.S. Senate in New Hampshire, holds his hand over his heart during the singing of the national anthem as he waits to take the stage for his town hall campaign rally with Sen. John McCain at the Pinkerton Academy in Derry, N.H., on Monday, Aug. 18, 2014.