The United States, in response to advances in missile threats from Iran and North Korea in recent years, has become more invested in Navy cruisers and destroyers that carry a high-tech radar system and dozens of missile interceptors.
As a result, the ballistic missile defence destroyers and cruisers that carry the high-tech Aegis system are a growing capability that is in hot demand by military commanders across the Middle East, Europe and the Pacific.
"They give the capability to the combatant commanders that allows them to position (the ships) where there's a need, and we feel they're a pretty good investment," said Admiral Bill Gortney, commander of US Fleet Forces in Norfolk. Unlike other missile defence systems, he said the ships are "able to sail to where the crisis is."
Dr Anthony Cordesman, a national security expert at the Centre for Strategic and International Studies in Washington, said the ships provide a layered defence that can quickly provide warning and details of a missile launch in areas of the world where there may be only a limited time to mount a response. And they present an added complication and deterrent for an adversary such as North Korea or Iran that may be trying to target a nearby US ally - such as South Korea or Israel.