Also note that the cops are in much more danger of life and limb than the rest of us. That is, the cops get to confront the creeps so that most of us don't have to most of the time. Some of those creeps are armed, violent, and not inclined to cooperate with the cops. This leads to cops often being in situations where, if they're a half-second late in shooting, they're dead. If they're a half-second early, they're villified, suspended and charged with manslaughter.
We're asking them to do the impossible, and they're coming close to doing it. I get the bit about trying to recalibrate the public's perception of risk, but don't make them freak out about the cops to make your point.
If you go by deaths (admittedly, a terrible metric since cops wear body armor and typically can get on the radio for an ambulance pretty quickly), then cops are not in more danger of life and limb than the rest of us. There are plenty of jobs that you are more likely to be killed, even murdered, in.
Regardless, you are missing the point of the comparison. The comparison should not be taken to imply "You should fear the police". That would be an irrational takeaway from a comparison between police and terrorists. What you are suppose to take away from the comparison is "Gee, my fear of terrorists is pretty damn irrational, since plenty of other things are more likely to kill me, but I don't particularly fear any of them."
The fact that so many people get hung up on this comparison demonstrates the comparison's relative uselessness in practice. The comparison has too much emotional baggage to be properly digested without careful spoon-feeding.
We're asking them to do the impossible, and they're coming close to doing it. I get the bit about trying to recalibrate the public's perception of risk, but don't make them freak out about the cops to make your point.