For those who've read my previous questions, you might begin to see a "subtle" recurring theme.
You can skip this part if you're just interested in the problem.
In a near-future post-WW3 world, a little less than 1 out of 1000 people is a mutant. Not (necessarily) the gross-green mutant type, rather the human with super-ability type. Geopolitics worldwide can be basically explained by a generalized cold war, with no peace treaty signed, but enough powerful mutants on each side to keep some semblance of status-quo. Less powerful mutants live a "normal" life. The rest are basically super-heroes against super-villains.
Let's set the scene. 50 people are in a urban non-descript location (a bank, a street, an opera), when Bad Guys A, B, and C come in, guns blazing. They want to rob/murder/take people hostage.
What you see in a Hollywood movie is, usually, people fleeing in every direction, screaming, panicking, with no organization and little to no care for others.
In reality, things seems to be a bit different. I looked into some papers to get a basic idea, so I've only got second-hand knowledge (thus, feel free to correct me if I'm wrong). But, apparently, a lot of people just stay there, stunned by what's happening. There are a few heroes helping others (diffusion of responsibility), a few quick ones who react and run away (probably a better capacity to deal with stressful situations, by my own interpretation), but most people just stay frozen during the first shock.
The question is: what would happen if out of these 50 people, more than 40 of them had basic military training? A mandatory national service exists, so apart from children and people too old when the measure was passed, everybody has been through at least conscription period. Would we observe a difference in reaction? Would the proportions change? More heroes, more runners, less frozen people?
They know help is on its way. People trained and equipped to react will be coming to deal adequately with the situation. Would they (statistically) be inclined to try to take matters into their own hands, or react in a disciplined manner and fall back until backup is there?
TLDR: Statistically, would we observe a significant difference in the way people react to a crisis situation when most of them have received military training, and if so, what kind of difference?
I'd prefer answers backed up by facts and/or studies, but I admit I failed to find any on this particular scenario. I'm not qualified in behavioral studies, so information in this question is to be taken with care, as I may have misunderstood some things.
EDIT 1 : The first answers focused a bit on the duration of the training. While it's my mistake and the answers are helpful on their own, keep in mind the question was more about trained vs untrained rather than duration of training (difference that has been treated in many answers, though in different arguments). I've revised the duration and put a more generic term to allow answers not to focus on the amount of time of the conscription.
The training is the same for everyone, and will likely include at least a few exercises about attack in civilian places. In this setting, the goal is not to have an army made of conscripts (and thus all of its roles), but to reinforce national identity and have everybody to be trained more quickly and efficiently than without conscription.