I'm from a very hick part of America and I know probably half a dozen people who used a phrase something like "unlocked doored, locked and loaded shotgun." Not exactly condoning that phrase, but the thief in hillbilly parts of America is gonna have to use force eventually if they want to steal from an occupied home whether it is locked or not.

I went into my uncle’s unlocked house and found myself staring down the barrel of his roommate’s gun. People don’t tend to go into occupied houses in the US as there is a very real risk of getting shot.

Not here in Sweden.

RC2 (resistance class 2) is to resist attacks with hammers, wedges and screwdrivers for three minutes. RC3 is to resist five minutes of crowbar attack RC4 is to resist power tools for 10 minutes

They're often made largely out of steel. I think RC3 is most common, but that RC4 is very rare.

i guess? i find most people knock like normal though. i have a good few guns though so i'm fully capable of defending myself. i never figured a residential grade lock was much good against someone anyway and if i'm right there it's not like someone can sneak in. i might be more worried if i was a small guy or a woman but i've never had a problem.