There're no more what ifs. The madman was amassing the troops on the border for months, dismissing any possibilities of preparing an invasion. Then invaded, and openly blackmailed the rest of the world with a nuclear strike, all spreaded by his chief "diplomat".
Present day russia as state proved to be pathologically incapable of maintaining signed treaties.
If anything, the diplomacy needed to rely on the effective sanctions. However, that's were the failure was. Since the 2014 the sanction pressure proved to be insignificant to alter russia's course. Did we get a second chance at it now?
Why do you need troops if you're not going to amass those? Still does not mean that diplomacy can't be useful.
The mental health argument is weird. Was Bush a madman when he invaded Iraq?
The point of sanctions isn't deterrence. It's to weaken the Russian economy and slow down the rate at which they can manufacture more weapons.
With such strength of diplomacy, no wonder it didn't work.
And yeah, you should've got by now that the position of your neihbours is the most important factor in the policy of most, if not all, countries.
This represents the total failure of diplomacy present in today's discourse.
We no longer think diplomacy affects the outcome and we think that any compromises from our side is just "free stuff" for the other one.
What happens if Putin is not insane? What happens if there were better diplomatic outcome to this situation that the war? The ones that were missed by the lack of effort?