I've been tried reading about how degrowth can safe the planet - personally I don't buy stuff I don't need, uses public transport extensively, etc. it happens to me naturally - But I don't see how people and countries can apply degrowth without fear that others in our capitalist world would take advantage.

For example. let's say the suddenly the UK decided to degeowth and stop making so much investments into the industrial sector. The international investments would simply go to countries that would accept the investments. It feels like degrowth is stuck in a prisoner's dilemma. And there's no obvious way around it.

How can this be solved?