The Times report says Russia was warned, but it doesn’t say the mercenaries were warned. I believe Amir said the mercenaries were told not to advance any farther but they did anyway. I don’t think Americans would ever make a mistake like that, to not warn the actual people involved, whoever they were.
They spoke Russian. They were former elite forces in Russia. And Israel shipped the bodies back to . . . Russia!
It was not a mistake by us - we were protecting our own troops who were under heavy attack. A head on attack across open ground against a dug-in force with air superiority, artillery, and close air support is a bad idea.
Despite the fact that we are even more deployed now than we were then, there has not been another incident. They learned that lesson the hard way!