tom swift among the diamond makers

So operation delta force was the first anti terrorist attack unit. With a special way of picking out their troops but they not only did antiterrrists attacks they did almost anything the president need them for. They where the elite their selection program was very strange. What they did was pick people that where captains or other from other special units like the rangers or the seals then they would do physical training. They would have to go to different places on their map in this grid like way not seeing anybody but maybe someone else and they had to navigate rocky terrains almost mountains they had to go over.