The horrors of terrorism can seem so far away, whether it’s the 13 years since Sept. 11, 2001, or the thousands of miles between Maine and the more recent attacks.

Then, in an instant, it’s at your front door.

“I was looking right in the direction. I was headed back toward the finish line and saw them, one right after another,” Pam Bither of Westbrook said Tuesday, less than 24 hours after the finish line at the Boston Marathon exploded in front of her.

Bither, 42, was running in her third Boston Marathon. She finished in a brisk 3:38, with her 6-year-old daughter and two friends waiting at the end, across the street from the blasts.

“When it first happened, everyone around me just stopped in disbelief,” Bither said. “My first thought is, ‘Are they safe?’”

To Mainers so familiar with the marathon, or otherwise so familiar with the city, the answer feels too much like “no” right now. It is hard in the immediate aftermath to imagine feeling safe or good again, not after watching Monday’s events unfold in real time during an event so full of joy.

On Marathon Monday, people line the race course, from its start in Hopkinton, through neighborhood after neighborhood, before heading down Beacon Street and into the city. At Kenmore Square, when the traditional morning Sox game lets out, fans pour into an already overflowing crowd. At that point, there is only a mile to go in the world’s best foot race, and the crowd, together, pulls the runners along, passing them from one to the next, a chain of encouragement that stretches through to Copley Square.

It is a fully Boston moment, but one that the whole world is let in on – 25,000 runners from 90 or so countries and 500,000 spectators.

The marathon is special to Mainers, too, coming as it does on the first day of spring school vacation, on Patriots Day, a holiday celebrated only in our two states, a throwback to the time when we were part of Massachusetts. There were more than 200 Mainers in Monday’s marathon, with family members and friends cheering them on. Countless Maine students attending college in Boston were undoubtedly along the route, which becomes the city’s biggest outdoor party this time each year.

All that has been marred. Future Marathon Mondays will be a somber reminder of the lives lost or changed forever by the events of April 15, 2013. In time, we will be able to take some solace in the incredible work of first responders at the scene, of the volunteer doctors in the medical tent, and of the bystanders who jumped to action seconds after the first explosion.

But it’s hard now to focus on anything but the people who were killed, or who lay maimed in Boston hospitals. And it all feels way too close to home.

Ben Bragdon is the managing editor of Current Publishing. He can be reached at bbragdon@keepmecurrent.com or followed on Twitter.