Really Kissinger's main crime was "supporting" various wars or coups, which basically every secretary of state does, since there is no war or coup in which the US isn't supporting one side over another. However our actual ability to
force coups is quite limited, take for example our repeated attempts to overthrow tiny Nicaragua or Cuba - here with substantial military aid and funds and even some irregular forces, continued for over a decade, yet we were stimied by these tiny nations.
So people see this obvious impotence, build a mental wall around it, and then just assume that everything else that happens in the world is the result of the CIA pulling the strings on direct orders from people like Kissinger - who is the puppet master of the third world.
This ... is not good history.
US power has always been primarily soft power -- cultural and economic power. We can threaten to cut off aid, impose sanctions, pay bribes, etc. But most coups that that are "US backed" would have succeeded with no actual backing, and often the backing consisted of side payments and giving a greenlight to not impose sanctions on the coup plotters. This was actually what Hussein claimed, that he was given a green light by Rumsfeld. It's only for truly weak and unpopular regimes, or states undergoing existing legitimacy crises, that foreign meddling can be a difference maker.
Meanwhile, those times when the U.S. actually launches invasions of places -- Iraq, Afghanistan, Kosovo/Serbia, etc. are somehow discounted. Yeah, Kissinger backed violent groups and lobbied to funnel financial and military aid to places that should not have received it, but at the same time he didn't actually lie us into wars, unlike Powell or Albright or even Dean Rusk. IMO these three have much higher body counts, and we are just talking about the post 1960 period in US diplomacy, and haven't even touched things like the Mexican-American war or adventurism or "felling trees and indians". It's just bizarre how much focus Kissinger has gotten, and I really do attribute it to self-promotion.