It might be helpful to go to pages 342 and 342 of her book Living History, in which she describes her trip to Tuzla:
I spent the hour-and-forty-minute flight wandering around the cavernous metal belly of the huge transport plane, chatting with the crew and members of the press corps, who were strapped into benchlike jump seats. It was like touring the inside of a blimp, but louder. The pilot, then one of just four female C-17 pilots in the Air Force, kept the plane cruising high over the devastated countryside, above the reach of surface-to-air missiles and sniper fire. As a reminder of the dangers that remained despite the official cease-fire, each of us was required to wear a flak jacket on the plane, and the Secret Service moved Chelsea and me up to the armored cockpit for the landing, Above the airstrip, the captain dipped a wing and made a near-perpindicular landing to evade possible ground fire.
Security conditions were constantly changing in the former Yugoslavia, and they had recently deteriorated. Due to reports of snipers in the hills around the airstrip, we were forced to cut short an event on the tarmac with local children, though we did have time to meet them and their teachers and to learn how hard they have worked during the war to continue classes in any safe spot they could find. One eight-year-old girl gave me a copy of a poem she had written entitled "Peace." Chelsea and I presented the school supplies we have brought, along with letters from seventh-grade children at Baumholder whose parents and teachers had initiated a pen pal program. We were then hustled off to the fortified American base at Tuzla, where over two thousand American, Russian, Canadian, British, and Polish soldiers were encamped in a large tent city.
(The emphases in italics are mine, of course.)
I guess it's easy to confuse reports of snipers with actual snipers.