One thing that you have to realize about crime in the US is that something like 80% of our crime is gang related, especially violent crime. I live in Los Angeles, where many of the gang members are immigrants, or children of immigrants. I don't think that there are the same kind of gang problems in Belgium, are there? Is it possible there to deport immigrants who are criminals? We are supposed to deport criminal aliens here, but I am not sure that it is always possible.
In areas of the US where there aren't very many gangs, there isn't much crime, like North Dakota or Montana. There are almost no homicides there either, but if you look at an area with more gang activity, like Detroit, Michigan, they have extremely high homicide rates.
As for car theft, I think that we have a lot more cars per capita here. This alone probably explains why I am living in the car theft capitol of the world.