Absolutely not.
Legitimate purposes for a gun include shooting at targets and murdering wildlife. They do not include shooting at people or intending to shoot at people, for any reason. Unless you are a member of the police or the armed forces. And even the police are not routinely armed, and not all police officers are trained or authorised to carry firearms.
What the US posters have to get their brains around is that we're happy about this. We do not want everyone, including the nutters, the disaffected teenagers and the boyfriend of the woman I asked to stop shouting outside my house at midnight last night to have guns. We consider the desire to keep a gun in the home or on the person for "self-defence" to be bordering on the psychopathic.
Whenever there is a shooting incident, the overwhelming outcry from the public is for even more gun control. If anyone suggests that perhaps legislation might be going a bit too far (Olympic target shooting teams for example), the retort is, you don't want this country to become like the USA, do you? And everyone shudders and backs off.
Rolfe.