One drawback is the cost. An interceptor missile costs $50,000, compared to just $500 for a Palestinian rocket.

VOA: standard.2010.07.20

"Standard Missile-3" interceptors will be placed on Polish soil, along with other interceptor missiles deployed on U.S.Navy ships in the Mediterranean and the North Sea.

VOA: standard.2009.10.22

He asserts that even if a missile interceptor succeeded in effecting a boost-phase "kill" on an incoming missile (that is during the early stage of its trajectory when it is moving relatively slowly, easily identified and vulnerable to destruction), its warhead might continue on and land in friendly territory with devastating effect.

CENTERFORSECURITYPOLICY: Strategy of a Thousand Cuts

Israel's defence ministry says it has carried out a successful test of its new missile interceptor system.

BBC: Israel successfully tests Arrow 3 missile interceptor

So Mr Martin said that he still expects to be consulted before any American interceptor missile is fired over Canada.

ECONOMIST: Stumbling towards a new world role