Even in the UK and in Norway police officers are allowed to carry gun's but they rarely do, and rarely have to. There are special forces who are called when wide-reaching bullet forces are needed, and even then deadly force is rarely needed to take out an attacker.
Third civilized countries have the principle of consequence of lawlessness. If a police officer oversteps his powers he has to face the consequences, otherwise he will continue to abuse his powers. A very simple but powerful principle, which is esp. needed for those who have state-granted special powers.
Forth, civilized countries invest a lot into marketing of police powers. TV broadcasts crime investigations and police dramas all the time, round the clock, where police is presented to serve the people, so they are presented in a positive light. This might be useful to cover up police abuse, but is in fact more useful as a positive role model to the enforcers. Officers stepping out of line are clearly overstepping their line. Whilst in the US the lone cop hero taking down the suspect with a well-aimed shot is the patriotic hero, saving the community from crime and violence. Marketing is different there, the state powers don't invest in these kind of TV dramas.