If you look at the selected ratios of debt to GDP for Canada, China, and Australia they've each grown tremendously since 2008/09. While this has helped goose growth in each of their respective economies (and spilled out into the greater world as well) it does not bode well for the future. The thing about debt is it need to be paid off. Somehow, someway (by default, payment or inflation) the ratios will drop when they reach such lofty heights.