Triangulation just isn’t Obama’s style, and his scolding of liberals seems to be rooted in genuine frustration with them for disagreeing with him about what’s politically possible, given today’s realities. To whatever degree Obama is using his disagreement with the left for positioning purposes, it’s more about temperament than ideology: His role is that of the voice of sanity trying to talk sense into uncompromising partisans on both sides. This just isn’t Clintonian triangulation in any sense.