The western world's quality of life requires endemic poverty in most of the rest of the world to be sustained. That poverty is created by western financial institutions and western militaries, which have built and enforce a global system of unequal exchange, where the trade systems between western and nonwestern countries are favorable to the western ones, to the tune of siphoning trillions of dollars from the nonwestern world every year.
It's really very simple. If capitalism worked, why hasn't it worked for the hundreds of countries that have done it for the past century in central and south america, africa, and asia?