Is there a ceiling to economic supremacy?

Donald Trump is doing everything he can think off to improve the US economy. Tariffs, cutting government spending, bringing manufacturing back home, accessing more resources and lowering the cost of energy. Will it work? And, if it does, Phil wonders whether there’s a ceiling to how far the US economy can grow. Or does it grow at the expense of other countries/ In other words, Phil wants Stebe Keen to explain what happens as the US, the world’s leading economy, tries to heighten its supremacy.