Archived NYT article:
"Mr. Kirk, whose appearances on college campuses drew ardent support and fierce condemnation, had received numerous death threats over the past year and had been traveling with a security team for months. Over dinner, Ms. Kirk implored her husband to start wearing a bulletproof vest. When he demurred, the friend suggested that Mr. Kirk speak behind bulletproof glass.
“Not yet,” Mr. Kirk replied. He said he felt confident in his team, and that there would be additional security at the Utah event. But Ms. Kirk, like several of her husband’s subordinates, had occasionally heard him imply that his life could be cut short by violence. She found herself wondering if a part of him had already surrendered to such a prospect."