A subordinating conjunction usually introduces an adverb clause.
The last one. It makes most sence instead of the first three.
Roosevelt's use of rethoric in this excerpt advances his viewpoint in the followinf way:
By using parallel structure, Roosevelt draws attention to the reasons he is concerned about the dictators who have taken power in parts of Europe.
He presents six different noun phrases, all with the same grammatical form: <em>international generosity, return of true independence, world disarmament, freedom of expression, freedom of religion </em>and<em> good business.</em>
By using parallel structures, the text remains readable and clear, which helps to get the message across without any sort of confusion.
