Text on this US Marines site suggests to me this is just boilerplate stuff informing reservists and anybody reading of what they do if the Feds were to declare an emergency over some event such as , cyclone, volcanic eruption, floods yadda yadda -
and require manpower and military resources to assist victims as required.
https://www.marines.mil/News/Messages/Messages-Display/Article/1979422/manpower-guidance-for-activation-and-deactivation-of-reserve-component-rc-marin
some www sites may misinterpret or take their interpretations a few bridges too far.
