Why scramjets may follow ballistic hypersonic weapons

Could scramjet-powered hypersonic weapons avoid the identification risks of ICBM-derived systems?

Probably; ballistic-derived weapons may arrive first, but practical systems are likely to move toward scramjet propulsion.

Scramjets could eventually avoid some of the ambiguity created by launching a hypersonic weapon on an intercontinental-ballistic-missile profile. Ballistic-derived systems were expected to arrive first because they offered the quickest route to very high speed. Practical operational designs were then likely to migrate toward scramjets. That development path would directly address the concern that an ICBM-like launch can be misidentified before its purpose is clear.