Obama has realized that if he wants to maintain his enormous popularity among liberals, he can no longer just sit on the sidelines as Trump tramples all over his legacy.  At the same time, the last thing he wants to do is ruin his retirement and risk his pristine reputation by getting into a mud fight, since no one benefits more from those than Trump.  Thus he seems to have found a middle ground of mild criticism.

Trump reacted with a zinger about falling asleep.

When Obama fans heard about this, they went absolutely ballistic.

It’s not surprising they would become so angry.   They consider Obama to be the greatest public speaker of all time, so to have a man they consider unworthy of shining Obama’s shoes,  not only destroy Obama’s legacy, but mock even his greatest talent, just adds insult to injury.

Why are they so psychologically invested in Obama?  Because white liberals pride themselves in supporting the underdogs and thus being very pro-black, but for years they’ve struggled to find a black they can get excited about.  Rap stars and athletes are too uneducated for their elitist tastes.    Even Oprah struck some of them as tacky for celebrating diets and materialism, and being loved by Midwestern housewives.

In Obama they found a black who looked, acted, and had the credentials of the white liberal elite, and thus he became their messiah.  By contrast, Trump is everything they hate (tacky materialism, uneducated speaking style, white working class fans) and is also a “racist” white conservative, making him the ultimate villain.