I'm no Kissinger expert, but maybe he was wrong? I mean, Cambodia alone shoud make us question his judgment. Or, like CoH argued, maybe his approach was right in the '70s but not useful now?
That is, maybe the better angle of discussion isn't who supported what position in the past, but what the strengths and weaknesses are of different policies in today's context?
By the way, I'm not sure why you're referencing Buchanan here. Maybe he was against negotiation and discussion with foreign, antagonistic powers in the past, but for the last ten or twenty years, he's been a pretty vocal proponent of dealing with Iran and Russia, and not poking them and backing them into a corner. He even implored Trump to keep the Obama nuclear deal with Iran:
The Israelis, Saudis and Beltway War Party want to kill the deal because they want a clash with Tehran. Don't let them.
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