There was no lack of self-control. We're so used to people talking nice, polite, and politically correct in Trek that when someone says something that isn't, it's apparently an outrageous and unforgiveable act. It might have just been that he was a Starfleet command-rank officer eligible for a captaincy. Although the Vulcans wanted Gardner to command Enterprise, in the end, though, it came down to Archer and Robinson. It's possible that it wasn't so much a case that Archer won command of Enterprise that Robinson lost it, IMO.
No, actually it sounds like something someone with common sense would ask. The scene was there, I believe, to show the contrast between the 22nd century humans and 22nd century Vulcans. However, the hamfisted writing coupled with Scott's total lack of subtlety and charm in his delivery, combine to bring Archer off as somewhere between and out of control hothead and a plain old idiot. Again, reacting to something a Vulcan says which is perceived as an insult, by returning an inuslt or, even worse, openly threatening with physical violence is simply bad behaviour on it's face, "crucial" situatiion or not. So would most of us unless you're a pro wrestler or something. Splitting hairs between whether or not "I'm thinking about knocking you on your ass" (as opposed to "I'm going to knock you on your ass") is or is not a threat I guess works for argument's sake, but in reality, they're both likely to be perceived as threats. Whether or not he was there to be a diplomat is more splitting of hairs for argument's sake. Archer wa about to be the first human representative in deep space, a bit of natural diplomatic ability would seem appropriate. So the Vulcans in the meeting got off light, is that your point? So, are you arguing that Archer's harsh words really weren't that harsh, or we should be understanding of his lack of common sense because he wasn't as "polished" as those who would follow. Well, I guess if one sees Archer's words as "justified", "non-threatening", the result of self control, then I guess it is easy to understand why any complaint about his behavior might be viewed as a cry for political correctness.
Not really because it was a simple matter of tit for tat. No, objectively it was just Archer not responding nicely to a not very nice remark. Anything else is just bashing Archer for being Human and not perfect. Far worse things are said in even the most polite gatherings every minute.
Wow, where do you live? I do not want to go there. As we obviously can't change your mind on this, I suggest we divert the conversation. Let's talk about why the Vulcans were right.
Too late, it's the world we all live in. People say impolite or rude things all the time, sometimes in jest, sometimes not. Depends on where you are and the formality/informality of the setting (or the persons involved). What Archer said could even be considered by some as tame as even more "colorful metaphors" could have been used. Conversely, someone more stuffy than Admiral Forrest might have chastised Archer for what he said. Nah, the Vulcans were just afraid of how much progress Humans were making in such a very short time (by their standards). Compared to Humans, Vulcans were almost standing still by the 22nd-Century. "We had our wars, Admiral, just as Humans did. Our planet was devastated, our civilization nearly destroyed. Logic saved us. But it took almost fifteen hundred years for us to rebuild our world and travel to the stars. You Humans did the same in less than a century. There are those on the High Command who wonder what Humans would achieve in the century to come, and they don't like the answer." --Ambassador Soval to Admiral Forrest.