Whats the most decisive naval battle or incident in history?

The Battle of Leyte Gulf is the largest Blue water force VS Blue Water Force Naval battle ever, and it pretty much broke the back of the Japanese Navy in WWII.

I always thought the Barbary Wars were crucial, not that they were large engagements but it was the first time America stretched it arms overseas and the first time the American Flag flew over a Foreign port.

Of course it has been said before but Trafalgar will always be one that comes to mind.

Other ones that pop in my mind are The Battle of Lake Champlain, Valcour Island, Coral Sea, Santiago.