One more thought - it is also entirely possible these banal and insulting remarks are designed to instigate a hoped-for violent reaction, so as to put into motion that which Obama has already prepared.
Expect an increasing amount of such rhetoric in the near future from Obama.
The provocation of which you speak may be multi-pronged,
but I think the main effort is in riling up the “urban” base to attack white/conservatives to the point they fight back,
THEN they’ll bring the gov’t hammer down.