The US are trying it

No they fucking aren't

There have been US attempts to do things in the Mideast that at least partially were genuine attempts to do good things. Usually they don't turn out as anything good, because of massive structural issues both in the US armed forces and in the Mideast, so you could make the argument that we just shouldn't do anything ever. Which it seems like you're doing.

Our current type of involvement in the Israel / Palestine conflict is nothing resembling a benevolent attempt.

IDK why you assumed by "a separate military force" you assumed I meant US forces. I sort of agree with you that US military intervention would be unlikely to accomplish anything good (both because of the history and the low trust level they would receive, and because of the structural issues inherent in their priorities and behavior that have led to that low trust level).

IDK what form some kind of outside intervention could realistically take (I mean, aside from Iran deciding to blow up all Israel's cities and everyone gets to see what happens next, that's realistic on some level), but I wasn't saying US.