The problem here is that some twits did something like this once and since then everyone is saying "but look, they're doing it, why shouldn't we?" when they ought to be saying "we're all going to be imposing sanctions on that country until they stop doing that".

If someone is doing something, that's precedent -- but the precedent can either be "someone who does that can get away with it" or "someone who does that is not going to get away with it". And when making the decision, think through the consequences of everybody doing it to you if you allow it to be the first one.