There are 2000 Marines in Syria. Imagine, if Putin get angry and subjects them to the same treatment the Kiev Nazis subject allied PoWs to under CIA instructions. How would you feel then?
Putin can get as “angry” as he wants, but his wretched military is wayyy too ineffectual to act on that anger. Further… whether at the hand of disease or a pissed-off insider, he’s not long for this world. The sooner humanity is rid of him the better.