The short answer to your question is yes. The US has a system in Iraq and it works pretty well so long as it is not deployed inside cities or towns. It has to be deployed on the perimeters of the place to be defended only. It is currently in use at Baquba and the Balad airbase, among other places. None of this is secret. It is not 100% effective but it does save US lives in Iraq. Israel has it already but will not deploy it for political reasons.
One dead, three injured in Northern Arizona University shooting (DPA)
from the article: Intercepting Qassam rockets