Again, the Tmist cloud is spanning the entire globe. It has saturated not only the air, but the ground, drinking water. The amount of effort required to perform the cleanup would be massive, and if the Inhumans wanted to do anything they would still need to be granted access to the affected countries before they could perform such a task (unless done covertly of course).
So again answer my initial question. Is there any proof that would indicate the inhabitants of the earth know that it was 100% Black Bolt who was responsible? We as readers have that privilege; however, there could have been a saboteur or anything, an accident that resulted in the explosion. None of this is known by the general Marvel 616 earth population unless there is evidence to suggest otherwise. To the intent of Blackbolt, all of this is a moot point because none of the Xmen know what he did; it's not common knowledge. The same is not true for Magneto as he knowingly and inconspicuously attacked the New Attilian citizens recklessly and without a care in the world.
See my previous point. The Inhumans are not citizens of the Earth and going into other sovereign territories. Even if they wanted to do something it would have to be approved by those sovereign nations.
Ok so they are morally obligated. They still don't have to do anything.
At some point maybe the Inhumans will be called out for what resulted in this t-mist cloud debacle but at this point they have not. And I am speaking from a legal point, which I think has been the issue here. Someone may have the moral obligation to take care of those less fortunate than them; however, there is no law that mandates someone to do so. That has been my whole point. When large oil companies create environmental catastrophes due to oil leaks (unintentional/intentional) they have a legal obligation to correct the spills according to national governing bodies that exist to protect the environment. If these entities were not in place, businesses such as Exxon wouldn't have to necessarily clean a spill. That is why the creation of OSHA came about to ensure that there are regulations that people/businesses can be held accountable in an effort to prevent companies/people from doing nothing. Therefore, the Inhumans may have an obligation (morally) to do something because of optics or whatever, but they are not under any mandate either by a nation or worldwide to address the T-mist cloud situation. Even if they were mandated, they still don't have to comply because they are their own sovereign nation. This is why I think this situation based on everything that everyone knows on 616 earth is more an environmental crisis than an act of war BECAUSE there is no proof that the Inhumans are behind the crisis nor that it was a purposeful assault on the earth populous. So they don't have to do anything they can sit back and watch and enjoy the show unless otherwise authorized or mandated by the sovereign entities on earth. Which after that occurs, if they still do nothing it could then be deemed an act of war.
I agree that what the Inhumans are doing is selfish and does not promote a sense of concern of the mutants plight; however, they don't have to take up this "fight" to do anything for the reasons I mentioned to FuriousGeorge.
1.) I am not sure who did any of those things. I would assume he did it under his own capacities; however, him doing so, I would argue, was more of an act of war on Attilian than the inhabitants of earth.
2.) Of course not, but the thing is your analogy is flawed. You are assuming that Blackbolt's intention was for the mist to adversely affect the inhabitants of Earth. We know what a nuclear strike would do against people. There isn't enough proof that the mist in the form it is in would harm anyone adversely prior to the bombing, there is no proof that anyone (save Blackbolt and any others that may have witnessed his actions) on Earth that it was an inhuman responsible for the T-mist cloud, and at this point there has been no indication that any nation has publicly condemned the acts by the Inhumans and demanded that they do something about the the cloud. Posters here are saying they have to do something about the mist because we, as readers, are fully aware of everything that has occurred but that is not the case for the 616 characters on earth. Moreover, even if they felt the urge to do something, they would have to go through channels or at least do so covertly. At this point, they are not required to do anything about this mist.