Russia is trying to rebuild it's submarine fleet. Although nearly two hundred of their Cold War era nuclear boats are now awaiting dismantling, they still have about fifty subs in service. A third are ballistic missile boats, a third nuclear attack boats and a third diesel electric boats. At the end of the Cold War (1991), the Russians were sending ballistic missile boats (SSBNs, or "boomers") on patrol 37 times a year. The U.S. has sent out SSBNs on patrol 50 times a year for a long time. SSBN patrols usually last several months. The collapse of the Soviet Union in 1991 promptly led to a sharp cut in the defense budget. This had an impact on Russian SSBN patrols. By 1993, they were down to 19 a year. Throughout the 1990s, the number of Russian SSBN patrols continued to decline until, in 2001, there was just one and, in 2002, there were none. But this year, the patrols have resumed. The U.S. Navy, which tracks such things, refused to say what the exact number was. The U.S. and Russia have said that they no long aim their ballistic missiles at each other. The U.S. says their missiles are aimed at no one, but the guidance systems can be programmed with a target in minutes. The Russians decline to say exactly what they are doing.