Yeah... will note it again, so far as I've noticed if we're going to see nukes out of any non-minor actors, it's almost certainly going to be small yield (i.e. approaching that MOAB) and probably aimed specifically at military or insurgent targets. This, I wouldn't actually dismiss as a possibility, with the only likely candidates being russia or the US.
Russia potentially thinks it can get away with it (and they just might, with those qualifiers) and very well may be in a position to think it's worth the risk, particularly if the US and EU et al ramp things up in response to russian agitation or aggression.
The US, well, the US currently has the GOP at the head, and chunks of them have been courting the use of tactical scale nukes for at least a year or two now -- and trump has not exactly set himself staunchly against the possibility, not that it would have meant jack all if he had. Add on how much trouble the white house has been having on the administrative front and what that (and GOP and/or trump inclinations) is not terribly unlikely to mean regarding foreign relations, and the possibility of them deciding to drop a small one on, say, the development infrastructure of a thoroughly alienated Iran that's decided trumpian fuckery has gone far enough to say to hell with their agreements on their nuclear developments, is... not as small as I would like. Or something along those lines where the (near entirely) GOP aligned hawks decide to MOAB someone to similar effect, with shit breaking down from there.