Where I live, there's no such thing as a locked down school, be it primary school, high school, university, or college. There are security guards at the larger schools but they are not armed because they don't need to be. We very very rarely have anything like this happen. We do not have easy access to guns. You can get a hunting license and get a gun with a background check and what not. You can't just go into any random gun store and buy a gun without that. Now maybe in the USA due to how many psychos there seem to be with easy access to guns, you may need better security. But think about why there are so many psychos and why they can so easily get extremely dangerous weapons first. Here there may be the same percentage of psychos but you can't just go into any random sporting goods store and buy guns.