They can afford to. People are forgetting that unlike Russia, the US isn't in a wartime economy mode. Iran isn't a threat to world's most powerful military. And it's not as if Iran is suddenly going to launch a ground invasion against all its neighbours (which would be disaster for it). It too is seeking a stalemate end to the war. Iran's military has been crippled. The only problem is that as the Trump administration has declared victory, it's still trying to figure out what that "victory" is. And how to deal with Netanyahu's self-destructive tantrum that dragged the US into this mess in the first place.