First off, statistics:
For your analogy to be fair, you'd need to compare mortality among police in Chicago, not nationwide police mortality, since an officer, like a citizen, is under great threat in Chicago than rural Kansas.
Even so, you can compare the job to anything, and find statistics that sound more impressive. More children die via drowning in swimming pools than by gunshot wounds, but that doesn't mean that gun control discussions are immediately null and void.
I have been places in life, and known people, that have an intense hatred for cops and are happy to express their desire for an open season on them. People that if facing arrest for something small, will use any weapon at their disposal - gun, knife, vehicle - to get away. The fact that someone doesn't know of this world - it's not proof it doesn't exist, but simply a blessing for that person.
There are very, very bad people in this world, that if given the chance would take your MacBook, your iPhone, your iPad, and your money. "But but.. you don't understand! They'd never hurt me! I retweet about social injustice!"
There's some very, very bad cops who abuse their authority. But for someone to say that there's no danger is incredulous.