>>>It's fairly standard practice in the military to use Google Earth for air/ground coordination.

The US doesn't use Google Earth for fire support coordination, especially with combined arms assets (artillery, air, naval fires). We have dedicated software for that.

https://asc.army.mil/web/portfolio-item/advanced-field-artil...

https://dzone.com/articles/war-fighter-netbeans-platform

https://www.raytheon.com/capabilities/products/joint-automat...

This is relatively new then. In 2011, in the Marines, we were using Google Earth.

AFATDS and JADOCS were mature platforms when I learned them, also in 2011! Agile Client is newer to the Corps but has been used by the other services for a while. The problem with open-source geographic information systems is I don't think they are trusted/certified for accurate target mensuration. I don't have a good resource that explains exactly why/what the impacts could be, but I had a guy in the Fires Cell explain it that way once...

Sure, they could use private tags. But it's absolutely not standard practice to use public tags (that also need to be approved, and can be changed, by other google maps users).

Ah, I didn't realize that's what they're doing. That is incredibly stupid opsec.

They probably are not doing that. As others have pointed out, there are major hurdles to doing that.