Space warfare is hypothetical combat in which one or more belligerents are situated in outer space. The scope of space warfare therefore includes ground-to-space warfare, such as attacking satellites from the Earth; space-to-space warfare, such as satellites attacking satellites; and space-to-ground warfare, such as satellites attacking Earth-based targets. Space warfare in fiction is thus sub-genre and theme of science fiction, where it is portrayed with a range of realism and plausibility. no actual warfare is known to have taken place in space, though a number of tests and demonstrations have been performed. International treaties are in place that attempt to regulate conflicts in space and limit the installation of space weapon systems, especially nuclear weapons. From 1985 to 2002 there was a United States Space Command, which in 2002 merged with the United States Strategic Command, leaving the United States Space Force (formerly Air Force Space Command until 2019) as the primary American military space force. The Russian Space Force, established on August 10, 1992, which became an independent section of the Russian Armed Forces on June 1, 2001, was replaced by the Russian Aerospace Defence Forces starting December 1, 2011, but was reestablished as a component of the Russian Aerospace Forces on August 1, 2015. In 2019 India conducted a test of the ASAT missile making it the fourth country with that capability, and in April of that year, the Indian Armed Forces established the Defence Space Agency. During the early Cold War, a survivable reconnaissance asset was considered highly valuable. In a time before satellites, this meant building an aircraft that could fly higher or faster, or both, compared to any interceptor that would try and bring it down. Notably, the United States would introduce the U-2 spy plane in 1956. It was thought, at the time of its introduction, that the plane’s service ceiling of 80,000 feet would render it immune to Soviet aircraft, missiles, and radar.