This is a very generalized principle which is true of all contentious speech.
Hardly. In this situation we have people who have been killed over this very issue in the near past. We have clear expressions that people are willing to kill over this specific form of speech. That is not the general case.
There are cases where people are willing to kill over conduct, or perceived conduct, like the performance of an abortion, but the willingness to kill over simply speech is rare. At least in the US.
The Nazis, choosing to parade and march through a Jewish community, may irritate some person and this person may then act upon this irritation with violence but this is not sufficient to censor speech.
"The Nazis"? You mean people who dress up as the Nazi's did, or as the Nazi's never did, and spew some of the hatred expressed by the Nazi's?
You must know that in some countries speech like this is prohibited.
The atheists, choosing to march and demonstrate, may irritate some religious zealot, and the religious zealot may resort to violence.
"The atheists"? When is the last time some Christian leader in the US said it was proper to kill atheists over their beliefs?
Muslim religious leaders, in many places, mostly places the US and other Western powers have disrupted with their seemingly continual violence, are preaching that it is perfectly fine, in fact it is good, to kill people over this.
This is different from the people in a crowded theater in which we know this group of people to exist and reasonably know how they are likely to respond to someone yelling fire.
The problem is not people responding. If people respond and leave, yes they miss the movie.
The problem is that there is a chance that some people will be harmed, even killed.
The potential for harm is what makes the speech contentious. Unlike the examples you gave, people think there is a high chance for accidental harm, and that is why many think it is speech that can be prohibited.
The difference between the two scenarios is that one involves potential accidental harm and the other involves potential deliberate harm. But both are harms people engaging in the conduct should clearly anticipate.
You might not know if it true or not, but I fully know it is impossible for anybody to draw Mohammed, and claims that one has drawn Mohammed are lies.
No, it is their opinion this is what Mohammad looks like or it is their opinion this is Mohammad.
No, it is a delusion that the cartoon is Mohammed. It is just something drawn and called Mohammed.
And of course people are free to draw Mohammed morning noon and night. Nobody will stop you or interfere with you.
The speech here really isn't the drawing of Mohammed, which as I said people can freely do, the speech here is publicizing that you are going to draw Mohammed.
Advertisements that Mohammed will be drawn are lies.
Fantastic! Then the Muslims do not have any basis for being pissed off since, after all, nobody has drawn Mohammad.
I'm not claiming the people willing to kill over this are rational, only that they exist.
And I am not saying they have any right to do it, only that in the present climate, as has to be known, of massive US violence against Muslims for over a decade, there is a clear risk for doing something like this.
I don't think it should be prohibited, but the people who do it are playing with fire, and they are not free speech crusaders. They are bigoted morons, putting people at risk.