The United States of America and Saudi Arabian trade relationship has long revolved around two central concepts: security and oil. Throughout the next two decades, the 50s and 60s, relations between the two nations grew significantly stronger. In 1950, ARAMCO and Saudi Arabia agreed on a 50/50 profit distribution of the oil discovered in Saudi Arabia. In 1951 the Mutual Defense Assistance Agreement was put into action, which allowed for the US arms trade to Saudi Arabia, along with a United States military training mission to be centered in the Saudi Land.