I doubt that America is relevant to salvation history. It's just another nation of sinners, like every other nation. It had its day in the sun, then it declined. Many more nations might rise and fall before the End Times. We're not special.
It’s the Second Beast of Revelations, that came into the world like a lamb but changes into the beast that is in service to the first beast and the world into service to the first beast.
I do believe the SDA church properly identified the Second Beast