I believe that if America has been more proactive, we could have either limited or delayed the infection. As I remember it, the infection spread from Asia to America and hit Europe after us on the East Coast, at least that what I remember hearing from the reports.
So yes, if we had been more proactive and developed a response much more in line with the Ebola outbreak, i believe it could have been delayed or lessened.
It'll put hair on anyone's chest!