Well, you could argue that if the state did it, it's a technicality not to call it terrorism and the definition could be extended. But here the picture is completely different - the target is a legit militarily significant object (and not just some shoe factory or ration storage, but a whopping nuclear center), and the goal is to destroy the object, not to indiscriminately harm civilian population in order to scare them and achieve a political goal.
> When a recognized government does it, it's generally called a war crime.
That it is a war crime in the context of international armed conflict (or against humanity otherwise) doesn't stop it from being terrorism, just as a state actor committint genocide doesn't make it any less genocide, though that too is either a war crime or crime against humanity.
The Germans bombed the hell out of civilians indiscriminately all over Europe, including London and most other large cities in the UK years before the allies bombed German cities.
Retaliation-in-kind during open war isn’t the same thing as terrorism.
... by non-state actors. When a recognized government does it, it's generally called a war crime.