A targeted attack against a strategic resource, during a war, with no [direct] civilian casualties. This doesn't meet the common definitions of terrorism. This is equivalent to bombing train yards, not city centers. The best argument for it being terrorism is the civilians who may freeze to death this winter, but even that is dubious.
if it is by a state, then it could be considered 'aggression' -- the 'supreme international crime'.
as for the no direct / immediate civilian casualties part ("dubious") -- we can think of myriad examples of terror attacks and war crimes where the vast majority of civilians dying as a result of said attacks came later, even from 'indirect' causes -- dresden, hiroshima, nagasaki, al-shifa, etc.
but whether you decide to classify it as a terror attack, terrorism, war crime, or something better or worse, i think we should be consistent, regardless of who the perpetrator(s) is/are.
A terrorist attack is an attack perpetrated in a terrorist campaign. I don't think this really qualify, but i guess i could see why.
It could be a war crime though.