From my 5 year old: Why aren't nomad raids a thing anymore?

I was reading a book about the Silk Road with my five year old, and she was very interested in the description of Turkoman nomads raiding a caravan. She asked if there were still nomads and if they still raided caravans. I said that were still some nomads in Central Asia, although not a lot, but they didn't raid caravans anymore. She asked why not.

The two answers I was able to come up with were, basically, that were more police in the area to stop raids (i.e., the areas are under more effective control by a state) and that nomads aren't very good at raiding trains or boats and most cargo now goes on trains and boats so there were no caravans to raid anymore.

My vague sense is that the second explanation is mostly wrong, because: 1) nomads probably could raid a train fairly well; 2) lots of cargo in that part of world goes by truck which they could also probably raid pretty well; and 3) nomad raids stopped being a factor in Central Asia well before railroads/trucks were common there.

Is my first explanation right? If so, why are states better at policing Central Asia now then they were 1000 years ago? If not, then why did nomd raids stop?