In passing the Teller Amendment, the US was trying to prove itself different
from the European imperialist powers by not annexing territory as everyone
expected it to, but actually opposing imperialist oppression in the world. Of
course, pushing Spain out of Cuba would serve American interests even if
the US did not formally own Cuba. US business would still have a dominant trade
with an independent Cuba and pushing the Spanish out would create more a more
stable and safe shipping zone in the Caribbean. As events would show, US
behavior in the war did not exactly accord to the spirit of the Teller
Amendment, though Cuba was allowed its independence.