Edit: I realised that I spelled Pissingers name wrong in the title. Pity.
Kissinger was one of the most cartoonishly evil figures of the 20th and 21st centuries. For every crime the USA committed, every war, every coup against a democratically elected government, every genocide, every massacre, he was involved somehow or even directly responsible. He is one of the most evil genocidal maniacs in modern human history.
Here’s a video that describes some of that in the most polite way possible.
I found a YouTube link in your comment. Here are links to the same video on alternative frontends that protect your privacy: