America didn't have to go across the seas to make a lot of their money. There is quite a bit of foreign U.S military operations going on. Along with a hundred to nine hundred ninety nine million dollars with trade. Staying within the country does make money,but not enough than with trade outside the country.
Trading outside the country, has the benefits. With America trading with Spain, Norway, and other bordering sea countries of Europe, that is the most expensive route. The countries get the agriculture