The US military no longer needs air superiority to deliver precision guided, oppressive strikes.
The US is not the first country to produce hypersonic missiles like this (or more precisely a hypersonic unmanned glide vehicle) but analysts would do well to understand that this fundamentally changes what the US ground forces can accomplish without the traditional overwhelming air dominance US military doctrine usually requires... and it doesn't require the US military to learn new tricks either, this is a natural progression of HIMARS type long range missile artillery.
I think the only defense against a hypersonic guided unmanned vehicle like this is to keep moving and always be immersed in a sea of credible decoys... which in the end is the only real defense to anything threatening.