Diplomacy exists in a dual world of clarity and ambiguity. In a sense, it can be understood as a process clarifying points of ambiguity between two competing powers. 

Negotiators intentionally use the element of ambiguity for many reasons: they might want to bring rivals to the negotiation table, avoid a war, raise their leverage, force a rival to concede, or bring negotiations to an end.

So, diplomatic ambiguity is in itself neither a winning or losing tactic, but a tool that negotiators can use one way or the other.

Even before it began, it was clear the historic Trump-Kim summit