U.S. President Donald Trump's Golden Dome missile defense concept revives a controversial, decades-old initiative whose ambitious construction could upend norms in outer space and reshape relations between the world's top space powers.

The system is intended to protect the United States from ballistic, cruise and hypersonic missiles, and missiles launched from space.

Midrange “hit to kill” missile interceptors have had many successes on test ranges over the past decade, and Ukraine and Israel have proved their technological capacity to neutralize major missile at...