One of the two shocking shortcomings of the otherwise excellent FEMA manual about dealing with all sorts of different emergencies, is,
they never mention that you can buy radios, especially ham radios (for which one needs a license to operate legally). Sometimes, in times of disasters, phone lines come down and cell towers are destroyed. Under those conditions, if you don't have a radio, you aren't going to be talking to anyone. With ham radio, you can talk hundreds or thousands of miles, off a car battery and maybe ten or twenty yards of wire for an antenna (which you should have prepared beforehand anyway.)
(The other shocking, glaring shortfall of the manual is that they never so much as mention the possibility that one could even consider buying a gun and training how to use it should the need arise. No mention whatsoever.)
I have 2 theories about why FEMA doesn’t mention amateur radio:
1) the license thing
2) it’s harder for the feds to exercise control on the ham bands, unlike the other methods mentioned