NATO selling a few jets to Ukraine isn't enough.
- Impossibility of Putin preserving his army as it is today. Loosing so much material and troops that it does not recover ever again and, eventually, looses its stance in the world (and perhaps Putin is "retired").
- Getting into a stalemate that Putin simply cannot afford in terms of reputation and in terms of the economy.
- For a total victory, after a massive loss of Russian lives and an economic meltdown, Putin is somehow "retired" by a military junta.
Sadly, none of this happens with Ukraine still being a place to live, nor without anger and hate for generations, nor without an economic shock across the world. The alternative is reaching an agreement. Unfortunately, that cannot be done before a war takes place because it has been proven that giving away territory or accepting aggressions to have peace (e.g. Austria with Hitler) does not work.
If the propaganda is to be believed, Russia will surrender themselves, withdraw all their troops from the country, and Ukraine will magically be isolated from any future military aggression.
The reality, of course, just involves Putin slaughtering as many civilians as possible until Ukraine eventually concedes, or until Putin is able to assassinate most of the Ukrainian government and install his puppets. Surely Ukraine should fight back, what else could they do? But I only mention this to dispel the false beliefs that war is a one or two month event. It will lasts years, and many more people will die unfortunately. The large crowd of people with Ukrainian flags on their social media profiles are in for a disappointment.