Taylor Swift is opening up about a scary situation.

One week after canceling three Eras Tour shows in Vienna due to a planned terror attack in the city, the "Fortnight" singer broke her silence on the decision, sharing that it was "devastating" to not perform for her Austrian fans.

"The reason for the cancellations filled me with a new sense of fear, and a tremendous amount of guilt because so many people had planned on coming to those shows," Taylor wrote in an Aug. 21 Instagram post. "But I was also so grateful to the authorities because thanks to them, we were grieving concerts and not lives."

Taylor went on to provide insight into why it took her over a week to speak out publicly on the terror plot, which came to light when Vienna State Police shared in an Aug. 7 press conference that two men had been taken into custody for having "detailed" plans to carry out an attack. A third suspect was later arrested in the case as the investigation continued. 

"Let me be very clear," the Grammy winner explained, "I am not going to speak about something publicly if I think doing so might provoke those who would want to harm the fans who come to my shows."

Noting that her "silence" when it came to her Vienna tour stops—scheduled for Aug. 8, Aug. 9 and Aug. 10—was her "actually showing restraint and waiting to express yourself at a time when it’s right to," Taylor continued, "My priority was finishing our European tour safely, and it is with great relief that I can say we did that."

And Taylor credited the thousands of Austrian fans who gathered in the streets to sing her music anyway with inspiring her to make a few security changes behind the scenes for the U.K. concerts that followed. 

"I was heartened by the love and unity I saw in the fans who banded together," the 34-year-old said. "I decided that all of my energy had to go toward helping to protect the nearly half a million people I had coming to see the shows in London."

Noting that her Eras Tour team "worked hand in hand with stadium staff and British authorities every day in pursuit of that goal," Taylor expressed her appreciation for how well her remaining five tour dates at London's Wembley Stadium turned out.  

"London felt like a beautiful dream sequence," the singer shared. "All five crowds at Wembley Stadium were bursting with passion, joy, and exuberance."

Taylor added, "The energy in that stadium was like the most giant bear hug from 92,000 people each night, and it brought me back to a place of carefree calm up there."