[Mr. Jeeves]

Nixon wanted to use the IRS as a weapon, and failed. For that, he is reviled. Obama is successfully using every federal agency that exists as a weapon. For that, his critics are called racists.

Nixon stupidly verbalized his ruminations. Obama wisely says nothing at all about his actual directives to agency heads...they just sort of intuitively understand (with an assist from Valerie Jarrett's flying monkeys) what he wants done to his enemies and act accordingly. And they all seem to be willing to fall upon their swords for Greater Socialism if discovered, fearing the wrath of the Hive more than any punishment Congress or the judiciary can inflict upon them.

[bert]

Obama is at arms length from the government

All the dirty work is at the behest of the various Czars put in place for the specific purpose of deniability

[wbill]

they just sort of intuitively understand

This.

Did BO say, "Go get those Evil Tea Party Guys"? Maybe. But what he definitively did was create an atmosphere where the folks in charge at the IRS a) Wanted to even up on Conservative groups and b) Knew that they'd get away with it.

Ditto any number of other abuses of power - voter fraud, EPA restrictions, Gun-Runner, et al, ad infinitum.