Russia cannot oppose America. But harm may. Russia is acting like a terrorist, suddenly and secretly. Open confrontation she was afraid.
It seems to me like you are from Ukraine. In that case, I am not surprised by your post. In Ukraine, Russia was only responding to the provocations created by the US. The Western Ukrainians were used as pawns by the Americans. They were unceremoniously dumped, once their use was over.
As a provocation it is possible to arrange on-site. If on the territory of Russia will come the army of Saudi Arabia to protect Chechnya? No Russia is the aggressor and you don't defend.