Answer:
Indeed, the freedom of maritime transportation was a very important issue for American economic interests.
In particular, the freedom of the seas implied that no nation, especially no European power such as Britain or France, controlled the maritime territories considered to be the high seas. Thus, once outside the territorial seas in which each nation exercised its sovereignty, each nation could circulate freely through the oceans, taking its products through ships to other nations.
The freedom of the seas allowed the United States to trade with other nations without limitations of any kind, nor to have to pay fees to other nations.