I think the US finally realized they can not compete in a globalized world and keep 8000m people obedient and dependent, so the push to partition the world to remain relevant and competitive has now come.

What's worse is that the US is fully aware this could result in another European war, and they coldly calculate that the US mainland would be entirely spared of damage, and that the US would be the single condition for the rebuilding of Europe with unpresedented control over politics, trade, and economy.