The US military has finally switched off ad tracking on the phones and computers it issues to its soldiers. Not over privacy. Because hostile states had already used that data to find American troops in the field.

In a letter sent to Senator Ron Wyden, it was confirmed that the Army, Air Force, Navy, Marine Corps and Special Operations Command have disabled the advertising identifier on all official devices - iPhones, Android phones and Windows computers across the entire military network. The Air Force did it last, only in July.

The mechanism is simpler than it sounds. Every phone carries an advertising identifier that apps read and pass on. Location data from those apps regularly ends up with third-party firms and data brokers, who then sell it on the open market. When the identifier is off, that soldier's location melts into the sea of every other switched-off device - it is hard to pull one specific person out of the pile.

Wyden raised the issue earlier this year, after establishing that foreign adversaries had targeted American soldiers in the Middle East using commercially purchased location data. Not hacking, not signals interception - purchasing. The same market on which any advertiser can pay to find out who moves where.

Here is the part rarely said out loud. While the military closes this channel for its own people, American intelligence agencies and the FBI openly admit they buy the same data for surveillance and intelligence work - without a court warrant. So the problem is not that the data exists. The problem is who is buying it. When an adversary buys it, that is a threat demanding an urgent measure across the entire armed forces. When your own agency buys it, that is a working method.

Even after the change, Wyden warned that the personal phones of soldiers and of outside contractors entering bases remain an open door. The official device is protected; the person carrying it in their pocket is not.

It is worth noting what the solution actually was. Not a new law, not a ban on the brokers, not a penalty for anyone - but switching off one field in the settings of official phones. So that entire market stays exactly as it was. Only the devices of American soldiers left it.