it's rakia, distilled by stefka's husband todor.the radilovs, this is supposed to be a day of celebration. but there's something bothering stefka, the nato maneuvers taking place in the mountains nearby. >> they scare me -- they really do. russia is not a weak power -- it's strong. reporter: but the presence of american forces is supposed to give bulgarians a feeling of security. reporter: joey donado is here to protect bulgarians like the radilovs. the 24-year-old u.s. marine corps sergeant is part of a tank unit at the novo selo training ground. this is also a special day for him. he's taking part in nato field training exercises with bulgarian troops. they've been training for it for more than two months. >> we have a great training area that allows us to move around with our tanks, as well as bulgarian mechanized units. it's a wide-enough space that we can do it together instead of one tank at a time or a few tanks at a time. reporter: he and the other infantry marines have been here since august. more american combat tanks arri