However what's the alternative?

Not arbitrarily pulling out of the seemingly workable agreement with other countries?

In this particular case, country B and country A have both behaved terribly at various times.

Economic sanctions might work as a sudden shock action.

Long-term sanctions are likely futile. There's a point at which the domestic economy compensates. They buy from other players, they learn to do without, they grumble and suck it up, but it doesn't evoke a reaction anymore. I also suspect the tendency to roll them out as "we're sanctioning 13 specific people in the cabinet and their companies" in waves until we finally actually impact everyday civilians doesn't help-- it's basically saying "brace for impact" to the population.

I suspect there's an entire generation or more of Cubans and Iranians who just grew up assuming "this is our economic normal" and don't really see it as a direct call to action of "if you'd be so kind as to remove your leadership, we'd buy your products."

Now, if you spend as much time as possible getting nations to build and maintain deep economic ties with each other, THEN pulling the plug suddenly and boldly, can have an impact. There's more disruption and a clear inflection point.

I also suspect that a lot of civilians view sanctions as non-actionable because there are usually limited and absurd requirements for them to be lifted. I can't imagine, for example, any way Cuba or the DPRK gets out of sanctions without explicitly discharging their current leadership. At best, that's intrusive and insulting to a sovereign nation; at worst it's cheering on civil war and strife. The Iran nuclear deal, before it imploded, was a potential breakthrough here-- we gave them tangible, realistic milestones that could be achieved without a coup, and honoured the commitment.

Country A has zero legitimacy doing this if they have the exact same weapons of mass destruction. Their only argument would be that they are more responsible. It reminds me of parents punishing their kid for smoking while they are smokers themselves. No credibilty.

To pick an extreme example, do you seriously believe the US has less legitimacy in this respect than North Korea?

Yes, absolutely. The US is responsible for far more bloodshed than North Korea. How many coups were backed by the US government, how many nukes we have, our never ending war machine...list goes on and on. I don't think North Korea is anything more than a totalitarian dictatorship but I 100% would never believe what western media backed by US imperialist propaganda is telling me about them.

By the way, the South Korea's National Security Law still has the clause that "any person who praises, incites or propagates the activities of an antigovernment organization (that includes DPRK by design)... shall be punished by imprisonment for not more than seven years". And this clause is actually used (see Amnesty International's report https://www.amnesty.org/en/documents/asa25/006/2012/en/ ), so it's literally illegal for a South Korean newspaper to print anything positive about DPRK.

North Korea is a tiny dictatorship that has pretty much zero impact on my day-to-day or even month-to-month life.

On the other hand, the fingers of the US are everywhere I turn.

YES! NK never bombed my country. Please grow up and realize that you can not claim anything as long as your country act as a terrorist

Thankfully, that isn't how the world actually works. People are able to understand that any country, including the US, is composed of people who work on different things with different views, and that there are things US entities still say and do that can be valuable and trusted.

> there are things US entities still say and do that can be valuable and trusted

Yeah, sure. For some reason, the US enjoys some special privileges when it comes to the international politics.

How long has the Russiahoax been going, five years? For five years, every single media outlet in the US attacks attacks my country and blames it of all sorts of criminal activity, while not a single piece or evidence has been presented.

And for some reason, most of the Americans that I've talked to don't see any problem with that and won't call their government russophobic, so much for your "different views."

Why should anybody believe anything said by an American anymore?

The easy answer: "most of the Americans that I've talked to" vs. "anything said by an American"

I'll expand: In the country I live in, a country often touted as very highly developed, there are still a lot of people that have weirdly (uninformed) nationalistic views about certain topics probably due to some oddities of history. This is the case in every single country I've traveled to or lived in. No one is advocating for designing global policy on Russia based on the views of the average American. That has little to do with trusting Americans (or Britons, or any other nationality of a place with a violent history) on other specific issues.

It’s a nice app example in theory, but can you point to any examples where this is working in practice?

Iran doesn’t count because they were / are complying but the US is a bully.

North Korea is a good example of sanctions not working in every way that matters.

Humans are weird.

In the absence of a working solution, people would prefer a well-intentioned (but as you said non-effective) solution to NOTHING.

If you do nothing, people will yell at you to do SOMETHING.

Sure, doing the RIGHT thing is best - but until then doing something is better than doing nothing.

Not saying I agree, just that's the idea.

So true.

If you’ve got something and it functions, your job is done, move on.

What standing does Country B have to make such a request, and what is Country B's own WMD policy?

Country B is the one having many weapon of mass destruction and used it 2 times already.

And is the only country to have ever used such weapons in wartime, and on a civilian population, nonetheless.

I suppose you'd prefer that, instead, the entirety of Japan would have had to be bombed into oblivion using non-nuclear weapons, not to mention the extra loss of life on the Allied side that would have almost certainly occurred during a more traditional invasion that would have likely been necessary.

War sucks, and there are rarely good choices; it's nearly always going to be a choice between something truly awful and something just merely really bad. Nuclear weapons suck, but I dare say they saved lives -- on both sides -- when used in that instance. Of course, after more people had them, and we realized the implications of MAD, using nuclear weapons is (thankfully) more or less off the table for any non-suicidal nation.

There were other options besides just those two. Japan at the time would have accepted any peace agreement with just a single clause: that the Emperor would not be executed. Anyone else could be. This was a reasonable agreement to make since the US didn't execute him anyway. The war could have ended in the same state that it ultimately did with far less loss of life on both sides except for the US insistence on unconditional surrender.

USA is full of weapon of mass destruction. You may agree or not that policy but the sheer fact that is true means that most contries go for - Ignore it and hope they don't destabilize the region / world.