The parent comment is conspiratorial.
The Iraq invasion was stupid and immoral but there's no evidence it had anything to do with currency plans.
The Euro is indeed most likely to overtake the US dollar (although not anytime soon) but they are likely to remain close allies and the dollars status as a reserve currency isn't all upside anyways(it makes our exports less competitive)
Because control of the Euro is split between lots of argumentative, economically-varying countries who are instinctively more interventionist than the US.
