Can someone explain to me why Trump pardoned Arpaio?

I just heard about it and it boggles my mind. I mean really? Anyone have a neutral answer or something reasonable that can keep me from having an aneurysm?
I mean he's done some really dumb things, but for me this just baffles me.

I didn't find the right solution from the Internet.

References:http://www.mmo-champion.com/threads/2287...pardoned-Arpaio

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