To distract from the real. The Alice in Wonderland strategy. Create a bunch of imaginary rabbits for people go after and chance, and, like we saw with the O Birther movements, get at each other's throats if you didn't believe the latest rabbit. All of that fighting and chasing rabbits and you can shift people's beliefs around at whim.
The alt right were prime targets. They were already idiots with racist tendencies so they were easily manipulated with Euro-right thought. It was great for organizing them into the fantasy that Trump and Putin are the last hope for the white race.
I personally believe that Trump was more than just aware of it. After all he seemed intent on using it with his constant reminders that Cruz and Rubio are hispanic as well as reminding people that a judge ruling against him is hispanic. It is right up Paul Manafort's alley.
Sadly I see people equating it to simple PR when in reality its an act of war at the hands of an enemy nation. If its OK to allow foreign entities to manipulate our elections then we may as well just open the doors and l;et them fund and even vote in our elections