Having been a ham for 36 years as well as a Signal Officer, the government and the military can pretty much shut everyone down. An EMP can take equipment down fast unless one has it secured in a Farady Cage of some sort.
However, I seriously doubt that hams will be affected by this “test.” The EAS System is only testing radio and television as far as we know at this time. If they do diddlefritz with the hams we will know something is up with their plan.
As for CB, unless your running an illegal amp with your radio you won’t be talking far. Our CB frequencies are Japan’s emergency frequencies and thus CB is limited to 5 watts.