Compare the success of the Serbian "unsophisticated security systems" with the blunders of the Blairite "sophisticated" systems, which for 8 years allowed the UK to serve (quite openly) as haven for jihadi preachers and terrorists, leading to the bombing deaths of dozens of innocent Britons and the incredibly stupid killing of an innocent Brazilian.
It's easy to judge from afar, ain't it? If I were the cops, I'd have likely killed the Brazilian, too. Because he didn't listen and kept struggling. Tragic, but...
And if he had been a bomber, you'd be criticizing them for not killing him.