In one of his notebooks the Puritan Jonathan Edwards observed that “If we hold a staff in our hand we seem to feel in the staff.”  He was noticing that we are less aware of the wood in our hand than of the gravel on the path when it connects with the staff.
To put it differently, the things we hold become extensions of ourselves. In a way, our tools make new knowledge possible. We should remember, though, that every awareness comes at the price of other awarenesses. When you peer through a telescope you can see what is distant at the expense of seeing what is near at hand. Holding a staff means not having a free hand to touch the lamb's ear and feel its softness.
Michael Polanyi, in his book Personal Knowledge, says it like this:
“Our subsidiary awareness of tools and probes can be regarded now as the act of making them form a part of our own body. The way we use a hammer or a blind man uses his stick, shows in fact that in both cases we shift outwards the points at which we make contact with the things that we observe as objects outside ourselves. While we rely on a tool or a probe, these are not handled as external objects….We pour ourselves out into them and assimilate them as parts of our own existence. We accept them existentially by dwelling in them.” They're not the only ones to notice this. I recall a passage in Walker Percy, where Binx describes his fiancée, Kate, at the wheel of her car. She practically dwells in her car, and it is as though the two have become one.
“When she drives, head ducked down, hands placed symmetrically on the wheel, the pale underflesh of her arms trembling slightly, her paraphernalia—straw seat, Kleenex dispenser, magnetic tray for cigarettes—all set in order about her, it is easy to believe that the light stiff little car has become gradually transformed by its owner until it is hers herself in its every nut and bolt.” Everyone who has a favorite tool knows this. We learn to touch-type through repetition. Practice may not make perfect, but it makes us so familiar that we find ourselves regarding our oldest tools as having personalities. Perhaps this is because we have poured ourselves into them through constant use. You don't have to be an animist to start to think of tools as having souls.
So with the police: when our tools are tools designed to give us mastery over others, we find ourselves becoming habituated to wielding that mastery, and regarding everyone who challenges that mastery as a natural slave.
In the face of this presumed mastery, the resentment of the mastered is not at all surprising.
Evan Selinger wrote insightfully about the way tools of mastery like guns affect us in an article in The Atlantic a few years ago. I was especially struck by a line he cited from Bruno Latour:
"You are different with a gun in your hand; the gun is different with you holding it. You are another subject because you hold the gun; the gun is another object because it has entered into a relationship with you."We don't enter relationships without both parties being affected; both we and the gun are altered by this holding of the gun. Guns are very strong tools; therefore it takes enormous strength of character to wield one without being deeply and powerfully affected by it. The gun mediates the relationship between the one holding it and the one at whom it is pointed. This is not something anyone can easily control.
So if you give your police armor and military weapons, it should not surprise you if they begin to regard themselves as engaging in military activity. And it similarly should not surprise the police when the unarmed, un-armored populace feels that the police is not acting "to serve and protect" but quite the opposite.
I don't mean to exonerate anyone by these words, but to try to explain why right now there appears to be a growing hostility between the police and civilians. Police have a very hard job to do. Police officers I know have described long hours of dealing with people at their very worst, day after day. I'm impressed by how many police manage to keep calm and help to defuse potentially explosive situations, and do so repeatedly, every day on the job. And as more Americans own and carry handguns, it does not surprise me that many officers now wear bulletproof vests. They never know who might fire a foolish and angry shot, and they want to return to their families at the end of the day, alive and intact. That's not hard to understand.
But all of us face a hard choice. As I've argued before, we need good laws, and we need to maintain and enforce those laws. However, enforcement should not primarily mean the use of force, but a well-working judicial system, supported by good schools and watched over by excellent journalism. And we need one thing more: we need to become better people, to enact and inhabit the virtues we most wish to see in others. Intentional actions are like tools; as we dwell in them, they become the way we know the world, and, just as we hold on to them, they hold on to us.
This is what we should encourage in ourselves and in others. Not more and stronger weapons but better lives, lived nakedly and as unprotected from others as we dare. The armor we put on becomes the wall that divides us, and it becomes the lens through which we see some things, and because of which other things - like the humanity of our neighbors - becomes wholly invisible.
 Jonathan Edwards, The Works of Jonathan Edwards: Scientific and Philosophical Writings. Wallace E. Anderson, ed., (New Haven and London: Yale University Press, 1980) p.225
 Michael Polanyi, Personal Knowledge. 59.
 Walker Percy, The Moviegoer. (New York: Farrar, Strauss & Giroux, 1969) 232.