How has the US foreign policy changed in comparison with the pre-war time?

Before the war, the United States of America was a country predominantly occupied by its own economy. The United States did not get involved in world conflicts.

After the victory over the fascist bloc, the United States, thanks to its economic power, began to actively subsidize the countries of Europe, which needed money to rebuild after the war. Thus, these countries fell into dependence on the United States.

The United States began to consider itself a world power, actively intervening in world affairs. It is the United States that is the ideologist of the bloc against the communist ideology.