What continents/regions became important business markets for the u. s?

The region that became an important business market for the US is : Asian Region (especially the southern part)
There are a lot of developing countries located in this part of the region and many US products were sent there

hope this helps

“destroyers for bases agreement in the destroyers for bases agreement between the united states and the united kingdom on september 2, 1940, fifty caldwell , wickes, and clemson class us navy destroyers were transferred to the toyalbnavy from the united states navy in exchange for land rights on british possessions.” i hope this you .