To remind the context of these naval attacks, on 19 July #Russia announced:

> Starting from 00.00 Moscow time on 20 July, all vessels sailing in the Black Sea waters to Ukrainian ports will be considered as potential carriers of military cargo.

That followed Russia's exit from the grain deal, and is equivalent to declaring all these civilian ships military targets. Russia decided to deny Ukrainian grain exports, reinforced that message by hitting Odessa grain silos, and offered grain sales to Turkey and African countries on its own.

But what was largely missed back then was an equivalent statement from #Ukraine made on 20 July:

> As of 00:00 on 21 July 2023, all vessels travelling in the waters of the Black Sea towards Russian seaports and Ukrainian seaports located on the territory of Ukraine temporarily occupied by Russia may be considered by Ukraine as carrying military cargo with all respective risks.

Russians ignored it, believing Ukraine has no means to materialise such threat.

As we now see, it has. I think the Russian oil tanker was both tactical (logistics ship) and strategic target (message to foreign ship owners and insurers).