If you treat people bad, they'll treat you bad. If you nuke Russia, Russia will nuke you. It's the Nash Equillibrium where each party is faced with a game and certain situations call for your best move. But your best move should account for what I'll do, and that should be factored into your initial move.
Mutually assured destruction is actually a powerful deterrent. Do we know what the ex-admin's situation was prior to all this? Only then should we pass judgement.