<blockquote>Because hypersonic missiles now in development have no foreseeable civilian role and no likely military role outside of major war between nuclear-armed states, and because a hypersonic arms race would contribute to strategic destabilization, it would seem reasonable to seek a way to avert such a race. A ban on hypersonic missile testing could do just that with, most likely, little need for extensive negotiations on verification.</blockquote>
via <a href="http://thebulletin.org/argument-hypersonic-missile-testing-ban7412">The argument for a hypersonic missile testing ban | Bulletin of the Atomic Scientists</a>.