The weapon sounds like a ghostly radio.
This is the latest in a string of controversies surrounding explicit posts shared within private military Facebook groups.
Recorded phone calls suggest around 215 Russian mercenaries were killed by U.S. artillery and airstrikes in a battle in Syria on the night of February 7.
President Donald Trump has accused Democrats of putting the U.S. military at risk.
Similar actions have provoked a sharp response from North Korea in the past.
Cowanda Jones-Johnson told The Washington Post that Trump disrespected her son.
The U.S. faces five major threats in the modern world: Russia, China, Iran, North Korea and global terrorism.
"Every base supports either a specific security goal or overall regional stability," writes Tim Hibbetts, an A-6E, F/A-18C pilot.