I've been to Bonaire several times. I feel safer there than in most US major cities. I would not say there is a lot of crime.
The main problem seems to be as others said, leaving valuables in the car while it is parked at rural locations. The "perps" wait it out. Once you are in the water, they know they have some time to peruse through your stuff. Their school of thought...if it's locked, there must be somthing good inside.
On my first trip there, I locked up our rental van (at a dive site on the north side). We had left a save-a-dive kit (with a spare computer, and other "good stuff" inside), as well as a relatively inexpensive 35mm camera ($200.00) (hidden inside a folding back seat), clothes, sandals etc.
After the dive, we returned to find a smashed window. Save-a-dive was untouched-computer still there. The camera was gone. My girlfriend and I are not sure what was on the film
Our friend had parked next to us and left car unlocked. They had left $100 cash in wallet, under front seat. It was still there.
Anyway, the police indicated that there was not much hope, but they could provide us with a report, for insurance purposes. Unfortunately we had no insurance.
I called the car rental company, they wanted $350 for the smashed window (side, sliding window on mini van). Being mechanically inclined, I went to the junk yard and bought a window for $15. I fixed it myself and did not get charged.
We have had no troubles on seveal trips since then. We always leave the car unlocked with the windows down. We are extra careful when we are at rural sites where there are no other divers. Any cash I have with me goes inside a zipped BC pocket.
Andrew