Here’s a good article about how amateur radio operators use our hobby in public service, in the Amateur Radio Emergency Service (ARES), sponsored by the American Radio Relay League (ARRL).
The Atlantic Magazine: Hams Prepare
“Today the United States is home to more than 700,000 licensed amateur radio operators (including every member of my immediate family—I’m the only one without a ham-radio license, having failed the lowest-level technician test).
“Around 40,000 of them are part of the Amateur Radio Emergency Service (or ARES, pronounced like the god of war), a subset of the ARRL. There are branches all over the country, and ARES members are the hams that show up at the simulated disasters, ready to relay information wherever it needs to go. They helped out during disasters like Hurricanes Katrina and Sandy and the 9/11 terror attacks—they were the ones getting messages out even after the cellphone towers went down, overloaded by the family members of World Trade Center employees trying to reach their loved ones.” Read more…