Steps to expand missile defenses will cost $ 1 billion . Defense Secretary Hagel says that more missile interceptors will be deployed by 2020 . NEW : N. Korea rocket launch , nuke test , mobile missile and threats prompt ##s . `` The reason that we are doing what we are doing and the reason we are advancing our program here for homeland security is to not take any chances , is to stay ahead of the threat and to assure any contingency , '' Hagel said . U.S. to work with Japan to increase its capability to improve early warning , tracking .
Steps to expand missile defenses will cost $ 1 billion . Defense Secretary Hagel says that more missile interceptors will be deployed by 2020 . NEW : N. Korea rocket launch , nuke test , mobile missile and threats prompt ##s . U.S. to work with Japan to increase its capability to improve early warning , tracking .