The military leaders who ordered troops to garrison in illegal areas should be arrested, charged, and tried in an impartial court.

It's pretty telling that western media has been studiously ignoring war crimes committed by Ukraine. In fact, we never see western war crimes punished, if the Nuremberg laws were applied, then every post-war American president would have been hanged. Until the west starts holding itself accountable, it has no moral ground to judge others.

Putin can end this war by pulling back his troops

This will obviously not happen, so I don't know why people keep repeating this as if it has any meaning. The reality of the situation is that Russia will fight this war to the end, and all the west is doing is prolonging the war which results in increased death and suffering. The goal of prolonging the war is not to help Ukraine but to weaken Russia. This was the stated goal in the RAND study before the war, and was recently reiterated by none other than US Secretary of Defense Lloyd Austin.

Finally, Ukraine lost sovereignty when the west ran a coup there in 2014 and installed a far right regime in place of a democratically elected government.