Responding proportionally means you are always the one on the defensive and your opponent gets to decide the course of the conflict.

There should be a tit for tat response but the tit needs to be much larger than the tat to create the incentive for no longer attacking

That's simply not true. The US response to Pearl Harbor was proportional -- you attacked us, that's war, so now we're warring -- but that didn't mean staying on the defensive.

If it's known that Russia is using ships to attack Western infrastructure, blockading those ships is entirely proportional. A blockade, in this case, isn't so much an act of war, as it is a response to an act of war.