Well, EU NATO in Europe. Not the USA. Remember, Russia doesn’t do proxy wars, it only starts wars in Europe because it can’t risk attacking its avowed enemy, the USA...
Oh.
Kadryov is an illustration why Cossaks have been so valuable as a fighting force. Keep in mind that the Cossak mentality developed over a very long time period where the Golden Horde/Crimean Khanate main business model was hunting slaves for export, estimated to be 7 million in total.
“Remember, Russia doesn’t do proxy wars...”
Russia has a history of doing just that: For instance, the Korean War and the Vietnam War, just to name two.
But, that is not unusual, because proxy wars have been relatively common throughout history; and a lot of countries have waged proxy wars, including the US.