(A) Other countries would not trade with the United States.
(B) ** The United States now had clear access to world trade. The United States Navy also had clear sailing to defend United States interests all over the world.
(C) The army could now drive from the United States to Panana and this would save the goverment money.
EXPLANATIONS BELOW
Concept note-1: -The Panama Canal was one of the largest public investments of its time. In the first decade of its operation, the Canal produced significant social returns for the United States. Most of these returns were due to the transportation of petroleum from California to the East Coast.
Concept note-2: -Due to the American-controlled Panama Canal cutting across the center of the country, Panama was of major strategic importance to the Allied war effort, as well as the most important strategic location in Latin America during World War II.
Concept note-3: -The United States established diplomatic relations with Panama in 1903 following its separation from Colombia. That year, through the Hay/Bunau-Varilla Treaty, Panama granted the United States rights to a zone spanning the country to build, administer, fortify, and defend an inter-oceanic canal.
Concept note-4: -The canal permits shippers of commercial goods, ranging from automobiles to grain, to save time and money by transporting cargo more quickly between the Atlantic and Pacific Oceans.