Trump wants a Golden Dome over America. Here's what it would take

The U.S. military tests its land-based Aegis missile defense system in 2018. Such systems can track and intercept short and medium-ranged missiles but struggle against larger, more powerful intercontinental ballistic missiles of the sort used by Russia and China.

Experts are divided whether a new missile defense system for the U.S., inspired by Israel's Iron Dome, would be worth the cost.

(Image credit: Mark Wright/AP)