Toby Keith is in the middle of a 12-day, five-nation concert tour of U.S. military installations. It marks his 10th year to perform for the troops overseas on the tours sponsored by the USO and Armed Forces Entertainment. During the first four days of the current tour, Keith performed for more than 3,900 service members stationed in Bahrain and aboard the USS Abraham Lincoln, among other locations. During his decade of USO shows and meet-and-greets, he has participated in more than 210 events for the troops. His summer concert tour of North America begins June 14 in Salt Lake City.