It probably makes more sense to treat this as a kind of parallelling, rather than ellipsis.
The two sentences are
Poland sent soldiers to fight alongside Americans in Iraq
Poland is nonetheless one of the few countries still hosting North Korean workers over Washington's objections.
Ellipsis and parallelling shorten a sentence by removing duplicated word sequences: in this case, the word Poland. An alternative way of shortening the sentence is to replace the second occurrence of Poland by it. The use of a pronoun is an alternative method of shortening the sentence, not a precursor to applying ellipsis or parallelling. The omitted word when the sentences are parallelled is therefore Poland, not it.