Complex sentence: The W-71 nuclear warhead was a US thermonuclear warhead developed at Lawrence Livermore National Laboratory in California and deployed on the LIM-49A Spartan, a component of the Safeguard Program, an anti-ballistic missile defense system briefly deployed by the US in the 1970s.
Split into simpler sentences: The W-71 nuclear warhead was a US thermonuclear warhead developed at Lawrence Livermore National Laboratory in California and deployed on the LIM-49A Spartan Anti-ballistic missile. This was a component of an Anti-ballistic missile defense system briefly deployed by the US in the 1970s.