Handshakes are meant to be relatively simple affairs, at least in terms of their signalling function. “Shake hands on it,” we are told. “Shake and make up.” They have been used as a civilised greeting for at least 2,500 years. But Donald Trump is now in the process of redefining the handshake, transforming it into the opening salvo in a battle for supremacy.
Handshakes date back at least as far as Ancient Greece – and there are artefacts from that period featuring images of Herakles shaking hands with Athena. Glenys Davies writing

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