<P> See United States national missile defense for the history of DoD missile defense programs . </P> <P> According to the agency's web - page: </P> <P> The Missile Defense Agency's mission is to develop, test and prepare for deployment of a missile defense system . Using complementary interceptors, land -, sea -, air - and space - based sensors, and battle management command and control systems, the planned missile defense system will be able to engage all classes and ranges of ballistic missile threats . Our programmatic strategy is to develop, rigorously test, and continuously evaluate production, deployment and operational alternatives for the ballistic missile defense system . Missile defense systems being developed and tested by MDA are primarily based on hit - to - kill technology . It has been described as hitting a bullet with a bullet - a capability that has been successfully demonstrated in test after test . </P> <P> Ballistic Missile Defense Systems (BMDS) must be able to be operated in different regions of the world in order for the success of the MDA mission . The International Strategy was approved by the MDA Director in 2007 . The general strategy for international efforts is: </P>

The missile defense agency (mda) works with the combatant commanders