Comment by ithkuil

I think you nailed the analogy with mines and the distinction between legal and moral.

Putting morality aside and focusing only on language and semantica:

I agree that this action may be better described as military action with an associated risk of harm to civilians (like many military actions do) rather than a pure action against civilians with the purpose of terrorizing your enemy civilian population.

I don't think it's common to use the word "terrorism" to indicate acts whose purpose is to induce fear in your military opponent.

Perhaps "psychological warfare" or "intimidation tactics".

That doesn't forbid you from qualifying that act of aggression as exacting an unnecessarily high toll on innocent bystanders. You don't have to invoke the word "terrorism" if all you want to say is that an act is immoral.