Why cant the Cartel get arrested?

I always wondered this, many people may say well.. the police don’t know about it or they are to scared. Number one, why would you be to scared? Can’t you just get a swat team and the WHOLE police department to arrest these guys? Like, they post these videos online.. them killing people. Dealing drugs like they do in Colombia. Why can’t you just arrest them?

I don’t know if I’m being stupid or not. My mum says that some Cartel people are higher up then Police.. but still.. can’t you still just arrest them?