There is no ambiguity when it comes to war. Ambiguity begs for certainty and a lack thereof has historically led to war.
History is full of examples: Europe’s and the US’ ambiguity as to how they would respond to Hitler’s growing territorial expansion in Europe was certainly a contributing factor to World War II. In the same vein, US ambiguity toward Japan’s expansionist militarism in the 1930s clearly led to the Pearl Harbor attacks that started the war in Asia in 1941.