"making sure we have a missile defense system" 

Could be a quote from long ago when Reagan launched his star wars missile defense program. Sounds good, but the fact that there are now super sonic delivery systems capable of carrying nuclear bombs makes the pipe dream of missile defense simply a boondoggle for the defense industry, which by the way, has a revolving door of personal with the Pentagon.

Because of the multi-lateral development of military arms technology of such competing countries such as China and Russia, there is no more the unilateral superiority that the US once held. 

This reality demands new strategic US foreign policy thinking. Without a change, we shall all become sacrificial lambs to those in power thinking that the military use of nuclear weapons is a rational response to disagreements with sovereign countries with their own self-interests.

The future depends on changing away from archaic Cold War mentality. That will be most difficult, to say the least.