One of the objectives of the US National Security Strategy is to work with other states to ensure regional security.

National security strategy policy guidance document with WMD guidance it provides

United States Department of Justice National Security Division was created in 2006.

To the extent that one can argue that the United States has a coherent military strategy at all, yes, that sounds about right.

No. Those are not the three principals of the National Military Strategy. According to the Chairman of the Joint Chiefs of Staff in his briefing to the Joint Chiefs, The National Military Strategy of the United States of America: A Strategy for Today, A Vision for Tomorrow, the NMS (National Military Strategy) supports the National Security Strategy (NSS) and implements the National Defense Strategy (NDS). The NMS is, basically; to protect the United States against external attacks and aggression; prevent conflict and surprise attack; and prevail against adversaries. To read the unclassified briefing paper, see the link below.

The National Security Council in the United States is responsible for informing the President of the United States about breaches in the security of the country. They also advice the President about what to do in the case of this breach in security.