At least in nuclear terms, the world is now a much more complex place than it was during the Cold War, when the United States and the Soviet Union, now Russia, were the only two countries possessing nuclear weapons. Today, many other nations may have the ability to launch long-range nuclear missiles.

In order to combat a potential nuclear attack, the United States has been developing a space-based missile defense system for the past two decades. This defense system began under former U.S. President Ronald Reagan. His Strategic Defense Initiative (SDI) called for the development of laser weaponry that would orbit the earth to shoot down ballistic missiles. There is now even talk of the United States developing a fifth military branch, perhaps called Space Force, that would pick up where the Air Force leaves off.

In this edition of How Stuff Will Work, we will look at how some wars are already being fought via satellite, and the technologies that are being developed to fight wars in space!