I am Greek, so I cannot claim objectivity on the subject matter. But it is hard to refrain from pointing out a few points of interest, from a negotiator's viewpoint.
One does not need to be a negotiation expert to know that high emotions usually lead to mistakes. The Greeks have been campaigning for the return of the Parthenon marbles and their reunification with the monument they belong to, centuries after Lord Elgin amputated the friezes and took the facades. The campaign was always riding an emotional wave, with the obvious objective of rallying public support mainly in Greece, but also among philhellenes around the world and particularly in the UK. This type of campaigning achieved this goal, but failed miserably in achieving its primary goal, that of the return of the marbles. Emotional campaigns more often fail in achieving their stated goals, as reason gives way to sentiment, thus diminishing their legitimacy. But last Monday, the story turned around! UK prime minister Sunak cancelled the meeting with his Greek counterpart, reacting to Mitsotakis’ comments during a BBC interview. The latter did and said nothing that was not repeated several times in the recent past, to justify the emotional response of the former. Guess who looks reasonable and who looks unstructured and driven by emotion now…
A main obstacle in the dispute (probably the toughest one) is the issue of Ownership of the marbles. The British Museum claims that the marbles were acquired lawfully at the time of purchase. The Greek state treats Lord Elgin’s transaction with the Ottoman occupiers of Greece at the time, as outright theft. In this case, there is a very different interpretation of what is lawful from each side of the dispute. If a negotiation hovers around a single issue it is very hard to make progress, as both sides are not willing to move and just give in. This is especially true when the contested issue is subjective. Opinions are very hard to change.
Progress is more likely to take place if the dispute is placed in a wider context. The introduction of more parameters in the agenda may provide flexibility for both sides. This is what the Greek government did over the last few years. They parked the issue of ownership and concentrated on how practically the marbles could be relocated to the Acropolis Museum and be exhibited there. At the same time, the Greeks dropped characterizations such as “theft”, which inevitably charged the atmosphere. This change of tactics took the element of emotion out, it invigorated the process, legitimized the Greek cause and created political pressure on the UK government. Sunak’s emotional response is a symptom of this pressure. The British Museum’s legitimacy is now diminishing, and its position gets harder and harder to defend.
One last point: Sunak’s emotional response damages the relationship with an ally. It creates a deadlock that will be hard to get out of. When deadlock is created by those at the most senior level, it usually takes a replacement to unlock the deadlock. As Sunak's reelection is far from certain in 13 months from now (at the most), it seems that the Greeks will have to wait till they have a less emotional and more “in sync with the real world” interlocutor in front of them. They have waited for more than 200 years. They can probably afford one more…