If the scene refers to Nazi-Germany it can be perfectly plausible that they in fact DO represent the Reichstag. Any other capitol buildings are out of the question because that is NOT what the scene refers to. The fact that Americans don't know what the Reichstag is (which is a shame) doesn't mean that it CAN'T be referred to. Unlike many think, America is not the whole world.
A european, who knows our history would be perfectly fine with the explanation.