The real outcome is that it proves that engaging in diplomacy with the US other than the most limited forms such as stating your demands and accepting concessions is dangerous. Negotiation in itself is a risk.
In the past that was not true except for the most extreme fascist regimes like Nazi Germany and Imperial Japan. There was always some diplomacy that could be done, except for those 2.
This is because the U.S. hegemons have taken the position that people who don't obey them are 'the jungle' and don't have to be talked to. You saw this with Russia at the outset of the SMO.
In the 1990s, the U.S. started criminalizing any opposition to them, or anything that was outside of their frameworks.
This happened in Rwanda, where the U.S. said (and still says) that one side was criminal genocidaires, and the other side [the U.S.-backed side that started the conflict] was heroic, intervening humanitarians. Then, it relentlessly prosecuted the losing side, and still does.
The big test-case was Yugoslavia.
U.S./Germany fomented all sorts of insurrection inside Yugoslavia, and then criminalized the government when it tried to contain it. Then, it cooked up a big 'humanitarian intervention,' the kind that the United Nations was largely formed to prevent. China made a few noises about the legality of this, so NATO bombed the Chinese embassy. After NATO bombed Yugoslavia for 78 days, Milosevic surrendered, hoping to stop the bloodshed. U.S. then turned former Yugoslavia into puppets, using them to expand NATO influence.
Milosevic actually did a pretty good job of defending himself during his trial, and was holding is own. So they neglected his health, prevented treatments he needed, and he died in prison. This was a former head-of-state, who turned himself over to the Americans, being treated like some rat in an oubliette.
That was the beginning of the end of international law as we understood it in the post-war period. Because people didn't effectively challenge Yugoslavia, and then especially what happened in Libya, we switched over to a 'might is right' model of international relations.
The position of the U.S. and Europe since 2022 especially has been "we don't have to talk to them" in reference to Russia, or anyone really. This is a colonial mentality that was shared by the hard-line fascist countries of WWII. It is now being turned towards the any "Global South" country, or even European countries if the electorate doesn't vote for the "right" candidate.
In reference to FairandUnbiased's post, I think what we're dealing with here is the "native-American" model of international relations. Where the U.S. will talk and make treaties, with the full intent of breaking them, or even using negotiations to strike. They will sign treaties about land and important things, while in the background already planning the genocide that is to follow.
Several Native-American chiefs were captured and killed in North America enroute to 'negotiations.'
Hitler admired how the U.S. and Canada handled its "Indian question."