Also known as "Star Wars," it was a proposed missile defense system announced by President Ronald Reagan in 1983. It aimed to protect the United States from potential nuclear attacks by intercepting incoming missiles.
Related terms
Arms Race: The competition between two nations (usually superpowers) to have superior military power, which influenced the development of SDI.
Mutual Assured Destruction (MAD): A theory stating that if both sides possess enough nuclear weapons, neither would initiate an attack due to fear of total annihilation.
Deterrence Theory: The belief that possessing strong defensive capabilities can prevent adversaries from attacking due to fear of retaliation.