This sounds like precursor to war.
I doubt it. The Iranians are clever and cunning, and whilst the US/Saudi/Israeli alliance would win a war through both technology and strength of numbers, there's a considerable risk that the Iranians home grown missiles and asymmetric tactics could inflict material destruction on globally important oil and gas facilities, as well as risking inflicting embarrassing damage on the US 5th fleet from Iran's asymmetric naval warfare tactics. Moreover, much as the US love the idea of regime change, it hasn't been a compelling success in Afghanistan, Iraq, Syria, or Libya.
A full blown war creates new risks that China or Russia might choose to intervene or supply weapons, which both have been talked about but (as far as we know) not yet done. Given that Russia is an energy exporter, a good, destructive war in the Gulf would actually be in Russia's strategic and economic interest. China is an energy importer, and wouldn't want a destructive war in the Gulf, but could have an interest in arming and assisting Iran who would then be obliged to supply as much gas as China wanted to buy.
So rather than a precursor to war, this court case and public accusation is part of the endless tit-for-tat intended to keep the pressure on by both sides. The US believes Iran is aiding fighters in Afghanistan, this court case creates a very modest amount of difficulty for Iran, but continues to paint Iran as the aggressor in the mind of the US public, and thus justify further arms sales to the GCC countries, continued free issue of arms to Israel, and all the rest. In this context, it doesn't matter whether the hacking actually happened at all, what if anything was taken, nor even which country did it (eg a false flag attack). And for Iran, if they did do it, it is a message that says "we're still here, we're not going away, and we're not frightened of Uncle Sam".